diff --git a/Admin/Install/db.json b/Admin/Install/db.json
index 9dfd230..ff661aa 100644
--- a/Admin/Install/db.json
+++ b/Admin/Install/db.json
@@ -200,6 +200,32 @@
             }
         }
     },
+    "itemmgmt_item_attr_default": {
+        "name": "itemmgmt_item_attr_default",
+        "fields": {
+            "itemmgmt_item_attr_default_id": {
+                "name": "itemmgmt_item_attr_default_id",
+                "type": "INT",
+                "null": false,
+                "primary": true,
+                "autoincrement": true
+            },
+            "itemmgmt_item_attr_default_type": {
+                "name": "itemmgmt_item_attr_default_type",
+                "type": "INT(11)",
+                "null": false,
+                "foreignTable": "itemmgmt_attr_type",
+                "foreignKey": "itemmgmt_attr_type_id"
+            },
+            "itemmgmt_item_attr_default_value": {
+                "name": "itemmgmt_item_attr_default_value",
+                "type": "INT(11)",
+                "null": false,
+                "foreignTable": "itemmgmt_attr_value",
+                "foreignKey": "itemmgmt_attr_value_id"
+            }
+        }
+    },
     "itemmgmt_item_attr": {
         "name": "itemmgmt_item_attr",
         "fields": {
diff --git a/Admin/Installer.php b/Admin/Installer.php
index 8e84fde..8e6f57a 100644
--- a/Admin/Installer.php
+++ b/Admin/Installer.php
@@ -79,52 +79,95 @@ final class Installer extends InstallerAbstract
     {
         $itemAttrValue = [];
 
-        $id                       = $itemAttrType['color']->getId();
         $itemAttrValue['color']   = [];
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Red', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][0]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Rot', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][1]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Blue', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][2]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Blau', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][3]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Green', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][4]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Grün', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][5]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Yellow', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][6]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Gelb', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][7]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'White', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][8]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Weiss', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][9]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Black', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][10]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Schwarz', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][11]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Braun', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][12]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Braun', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][13]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Purple', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][14]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Lila', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][15]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Pink', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][16]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Rosa', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][17]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Orange', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][18]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Orange', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][19]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Grey', ISO639x1Enum::_EN);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][20]);
-        $itemAttrValue['color'][] = new ItemAttributeValue($id, 'Grau', ISO639x1Enum::_DE);
-        ItemAttributeValueMapper::create($itemAttrValue['color'][21]);
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Red', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][0]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Rot', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][1]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Blue', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][2]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Blau', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][3]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Green', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][4]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Grün', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][5]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Yellow', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][6]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Gelb', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][7]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'White', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][8]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Weiss', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][9]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Black', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][10]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Schwarz', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][11]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Braun', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][12]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Braun', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][13]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Purple', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][14]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Lila', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][15]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Pink', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][16]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Rosa', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][17]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Orange', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][18]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Orange', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][19]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Grey', ISO639x1Enum::_EN);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][20]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
+        $itemAttrValue['color'][] = new ItemAttributeValue(AttributeValueType::_STRING, 'Grau', ISO639x1Enum::_DE);
+        $id = ItemAttributeValueMapper::create($itemAttrValue['color'][21]);
+        ItemAttributeTypeMapper::createRelation('defaults', $itemAttrType['color']->getId(), $id);
+
 
         return $itemAttrValue;
     }
diff --git a/Controller/ApiController.php b/Controller/ApiController.php
new file mode 100644
index 0000000..a238882
--- /dev/null
+++ b/Controller/ApiController.php
@@ -0,0 +1,594 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   Modules\ItemManagement
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\ItemManagement\Controller;
+
+use Modules\ItemManagement\Models\AttributeValueType;
+use Modules\ItemManagement\Models\ItemMapper;
+use phpOMS\Message\RequestAbstract;
+use phpOMS\Message\ResponseAbstract;
+use phpOMS\Model\Message\FormValidation;
+use phpOMS\Message\Http\RequestStatusCode;
+use phpOMS\Message\NotificationLevel;
+use Modules\ItemManagement\Models\Item;
+use Modules\ItemManagement\Models\ItemL11n;
+use Modules\ItemManagement\Models\ItemAttribute;
+use Modules\ItemManagement\Models\ItemAttributeTypeL11n;
+use Modules\ItemManagement\Models\ItemAttributeValue;
+use Modules\ItemManagement\Models\ItemL11nType;
+use Modules\ItemManagement\Models\ItemAttributeType;
+
+/**
+ * ItemManagement class.
+ *
+ * @package Modules\ItemManagement
+ * @license OMS License 1.0
+ * @link    https://orange-management.org
+ * @since   1.0.0
+ */
+final class ApiController extends Controller
+{
+    /**
+     * Api method to create item
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemCreate($request))) {
+            $response->set('item_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $item = $this->createItemFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $item, ItemMapper::class, 'item', $request->getOrigin());
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Item', 'Item successfully created', $item);
+    }
+
+    /**
+     * Method to create item from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return Item
+     *
+     * @since 1.0.0
+     */
+    private function createItemFromRequest(RequestAbstract $request) : Item
+    {
+        $item = new Item();
+        $item->setNumber($request->getData('number') ?? '');
+
+        return $item;
+    }
+
+    /**
+     * Validate item create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['number'] = empty($request->getData('number')))) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item attribute
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemAttributeCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemAttributeCreate($request))) {
+            $response->set('attribute_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $attribute = $this->createItemAttributeFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $attribute, ItemAttributeMapper::class, 'attribute', $request->getOrigin());
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Attribute', 'Attribute successfully created', $attribute);
+    }
+
+    /**
+     * Method to create item attribute from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return ItemAttribute
+     *
+     * @since 1.0.0
+     */
+    private function createItemAttributeFromRequest(RequestAbstract $request) : ItemAttribute
+    {
+        $attribute = new ItemAttribute();
+        $attribute->setItem((int) $request->getData('item'));
+        $attribute->setType((int) $request->getData('type'));
+        $attribute->setValue((int) $request->getData('value'));
+
+        return $attribute;
+    }
+
+    /**
+     * Validate item attribute create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemAttributeCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['type'] = empty($request->getData('type')))
+            || ($val['value'] = empty($request->getData('value')))
+            || ($val['item'] = empty($request->getData('item')))
+        ) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item attribute l11n
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemAttributeTypeL11nCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemAttributeTypeL11nCreate($request))) {
+            $response->set('attr_type_l11n_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $attrL11n = $this->createItemAttributeTypeL11nFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $attrL11n, ItemAttributeTypeL11nMapper::class, 'attr_type_l11n', $request->getOrigin());
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Attribute type localization', 'Attribute type localization successfully created', $attrL11n);
+    }
+
+    /**
+     * Method to create item attribute l11n from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return ItemAttributeTypeL11n
+     *
+     * @since 1.0.0
+     */
+    private function createItemAttributeTypeL11nFromRequest(RequestAbstract $request) : ItemAttributeTypeL11n
+    {
+        $attrL11n = new ItemAttributeTypeL11n();
+        $attrL11n->setType((int) ($request->getData('type') ?? 0));
+        $attrL11n->setLanguage((string) (
+            $request->getData('language') ?? $request->getLanguage()
+        ));
+        $attrL11n->setTitle((string) ($request->getData('title') ?? ''));
+
+        return $attrL11n;
+    }
+
+    /**
+     * Validate item attribute l11n create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemAttributeTypeL11nCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['title'] = empty($request->getData('title')))
+            || ($val['type'] = empty($request->getData('type')))
+        ) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item attribute type
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemAttributeTypeCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemAttributeTypeCreate($request))) {
+            $response->set('attr_type_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $attrType = $this->createItemAttributeTypeFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $attrType, ItemAttributeTypeMapper::class, 'attr_type', $request->getOrigin());
+
+        $l11nRequest = new HttpRequest($request->getUri());
+        $l11nRequest->setData('type', $attrType->getId());
+        $l11nRequest->setData('title', $request->getData('title'));
+        $l11nRequest->setData('language', $request->getData('language'));
+
+        $l11nAttributeType = $this->createItemAttributeTypeL11nFromRequest($l11nRequest);
+        $this->createModel($request->getHeader()->getAccount(), $l11nAttributeType, TagL11nMapper::class, 'attr_type_l11n_create', $request->getOrigin());
+
+        $attrType->setL11n($l11nAttributeType);
+
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Attribute type', 'Attribute type successfully created', $attrType);
+    }
+
+    /**
+     * Method to create item attribute from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return ItemAttributeType
+     *
+     * @since 1.0.0
+     */
+    private function createItemAttributeTypeFromRequest(RequestAbstract $request) : ItemAttributeType
+    {
+        $attrType = new ItemAttributeType();
+        $attrType->setName((string) ($request->getData('name') ?? ''));
+        $attrType->setFields((int) ($request->getData('fields') ?? 0));
+        $attrType->setCustom((bool) ($request->getData('custom') ?? false));
+
+        return $attrType;
+    }
+
+    /**
+     * Validate item attribute create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemAttributeTypeCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['name'] = empty($request->getData('name')))
+            || ($val['l11n'] = empty($request->getData('l11n')))
+        ) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item attribute value
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemAttributeValueCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemAttributeValueCreate($request))) {
+            $response->set('attr_value_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $attrValue = $this->createItemAttributeValueFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $attrValue, ItemAttributeValueMapper::class, 'attr_value', $request->getOrigin());
+
+        if ($attrValue->isDefault()) {
+            $this->createModelRelation(
+                $request->getHeader()->getAccount(),
+                (int) $request->getData('attributetype'),
+                $attrValue->getId(),
+                ItemAttributeTypeMapper::class, 'defaults', '', $request->getOrigin()
+            );
+        }
+
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Attribute value', 'Attribute value successfully created', $attrValue);
+    }
+
+    /**
+     * Method to create item attribute value from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return ItemAttributeValue
+     *
+     * @since 1.0.0
+     */
+    private function createItemAttributeValueFromRequest(RequestAbstract $request) : ItemAttributeValue
+    {
+        $attrValue = new ItemAttributeValue();
+
+        $type = $request->getData('type') ?? 0;
+        if ($type === AttributeValueType::_INT) {
+            $attrValue->setValueInt((int) $request->getData('value'));
+        } elseif ($type === AttributeValueType::_STRING) {
+            $attrValue->setValueString((string) $request->getData('value'));
+        } elseif ($type === AttributeValueType::_FLOAT) {
+            $attrValue->setValueDecimal((float) $request->getData('value'));
+        } elseif ($type === AttributeValueType::_DATETIME) {
+            $attrValue->setValueDat(new \DateTime($request->getData('value') ?? ''));
+        }
+
+        $attrValue->setDefault((bool) ($request->getData('default') ?? false));
+
+        if ($request->hasData('language')) {
+            $attrValue->setLanguage((string) ($request->getData('language') ?? $request->getLanguage()));
+        }
+
+        if ($request->hasData('country')) {
+            $attrValue->setCountry((string) ($request->getData('country') ?? $request->getHeader()->getL11n()->getCountry()));
+        }
+
+        return $attrValue;
+    }
+
+    /**
+     * Validate item attribute value create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemAttributeValueCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['type'] = empty($request->getData('type')))
+            || ($val['value'] = empty($request->getData('value')))
+        ) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item l11n type
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemL11nTypeCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemL11nTypeCreate($request))) {
+            $response->set('item_l11n_type_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $itemL11nType = $this->createItemL11nTypeFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $itemL11nType, ItemL11nTypeMapper::class, 'item_l11n_type', $request->getOrigin());
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Item localization type', 'Item localization type successfully created', $itemL11nType);
+    }
+
+    /**
+     * Method to create item l11n type from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return ItemL11nType
+     *
+     * @since 1.0.0
+     */
+    private function createItemL11nTypeFromRequest(RequestAbstract $request) : ItemL11nType
+    {
+        $itemL11nType = new ItemL11nType();
+        $itemL11nType->setTitle((string) ($request->getData('title') ?? ''));
+
+        return $itemL11nType;
+    }
+
+    /**
+     * Validate item l11n type create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemL11nTypeCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['title'] = empty($request->getData('title')))) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item l11n
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiItemL11nCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        if (!empty($val = $this->validateItemL11nCreate($request))) {
+            $response->set('item_l11n_create', new FormValidation($val));
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $itemL11n = $this->createItemL11nFromRequest($request);
+        $this->createModel($request->getHeader()->getAccount(), $itemL11n, ItemL11nMapper::class, 'item_l11n', $request->getOrigin());
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Item localization', 'Item localization successfully created', $itemL11n);
+    }
+
+    /**
+     * Method to create item l11n from request.
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return ItemL11n
+     *
+     * @since 1.0.0
+     */
+    private function createItemL11nFromRequest(RequestAbstract $request) : ItemL11n
+    {
+        $itemL11n = new ItemL11n();
+        $itemL11n->setItem((int) ($request->getData('item') ?? 0));
+        $itemL11n->setType((int) ($request->getData('type') ?? 0));
+        $itemL11n->setLanguage((string) (
+            $request->getData('language') ?? $request->getLanguage()
+        ));
+        $itemL11n->setDescription((string) ($request->getData('description') ?? ''));
+
+        return $itemL11n;
+    }
+
+    /**
+     * Validate item l11n create request
+     *
+     * @param RequestAbstract $request Request
+     *
+     * @return array<string, bool>
+     *
+     * @since 1.0.0
+     */
+    private function validateItemL11nCreate(RequestAbstract $request) : array
+    {
+        $val = [];
+        if (($val['item'] = empty($request->getData('item')))
+            || ($val['type'] = empty($request->getData('type')))
+            || ($val['description'] = empty($request->getData('description')))
+        ) {
+            return $val;
+        }
+
+        return [];
+    }
+
+    /**
+     * Api method to create item files
+     *
+     * @param RequestAbstract  $request  Request
+     * @param ResponseAbstract $response Response
+     * @param mixed            $data     Generic data
+     *
+     * @return void
+     *
+     * @api
+     *
+     * @since 1.0.0
+     */
+    public function apiFileCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
+    {
+        $uploadedFiles = $request->getFiles() ?? [];
+
+        if (empty($uploadedFiles)) {
+            $this->fillJsonResponse($request, $response, NotificationLevel::ERROR, 'Item', 'Invalid item image', $uploadedFiles);
+            $response->getHeader()->setStatusCode(RequestStatusCode::R_400);
+
+            return;
+        }
+
+        $uploaded = $this->app->moduleManager->get('Media')->uploadFiles(
+            $request->getData('name') ?? '',
+            $uploadedFiles,
+            $request->getHeader()->getAccount(),
+            'Modules/Media/Files/Modules/ItemManagement/' . ($request->getData('item') ?? '0'),
+            '/Modules/ItemManagement/' . ($request->getData('item') ?? '0'),
+            $request->getData('type') ?? '',
+            '',
+            '',
+            PathSettings::FILE_PATH
+        );
+
+        $this->createModelRelation(
+            $request->getHeader()->getAccount(),
+            (int) $request->getData('item'),
+            \reset($uploaded)->getId(),
+            ItemMapper::class, 'files', '', $request->getOrigin()
+        );
+
+        $this->fillJsonResponse($request, $response, NotificationLevel::OK, 'Image', 'Image successfully updated', $uploaded);
+    }
+}
diff --git a/Controller/BackendController.php b/Controller/BackendController.php
index 52993dd..26cd8d1 100644
--- a/Controller/BackendController.php
+++ b/Controller/BackendController.php
@@ -50,7 +50,7 @@ final class BackendController extends Controller
         $view->setTemplate('/Modules/ItemManagement/Theme/Backend/sales-item-list');
         $view->addData('nav', $this->app->moduleManager->get('Navigation')->createNavigationMid(1004805001, $request, $response));
 
-        $items = ItemMapper::withConditional('language', $response->getHeader()->getL11n()->getLanguage())::getAll();
+        $items = ItemMapper::withConditional('language', $response->getLanguage())::getAll();
         $view->addData('items', $items);
 
         return $view;
diff --git a/Docs/Dev/img/uml.draw.svg b/Docs/Dev/img/uml.draw.svg
new file mode 100644
index 0000000..e69de29
diff --git a/Models/AttributeValueType.php b/Models/AttributeValueType.php
new file mode 100644
index 0000000..f0336f4
--- /dev/null
+++ b/Models/AttributeValueType.php
@@ -0,0 +1,36 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.4
+ *
+ * @package   Modules\ItemManagement\Models
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\ItemManagement\Models;
+
+use phpOMS\Stdlib\Base\Enum;
+
+/**
+ * Attribute value type enum.
+ *
+ * @package Modules\ItemManagement\Models
+ * @license OMS License 1.0
+ * @link    https://orange-management.org
+ * @since   1.0.0
+ */
+abstract class AttributeValueType extends Enum
+{
+    public const _INT = 0;
+
+    public const _STRING = 1;
+
+    public const _FLOAT = 2;
+
+    public const _DATETIME = 3;
+}
diff --git a/Models/ItemAttribute.php b/Models/ItemAttribute.php
index ebbe2f3..ebea096 100644
--- a/Models/ItemAttribute.php
+++ b/Models/ItemAttribute.php
@@ -70,6 +70,34 @@ class ItemAttribute implements \JsonSerializable, ArrayableInterface
         return $this->id;
     }
 
+    /**
+     * Set type
+     *
+     * @param int|ItemAttributeType $type Type
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setType($type) : void
+    {
+        $this->type = $type;
+    }
+
+    /**
+     * Set value
+     *
+     * @param int|ItemAttributeValue $type Type
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setValue($value) : void
+    {
+        $this->value = $value;
+    }
+
     /**
      * {@inheritdoc}
      */
diff --git a/Models/ItemAttributeType.php b/Models/ItemAttributeType.php
index 5d54faa..b051180 100644
--- a/Models/ItemAttributeType.php
+++ b/Models/ItemAttributeType.php
@@ -65,6 +65,13 @@ class ItemAttributeType implements \JsonSerializable, ArrayableInterface
      */
     protected $l11n = 0;
 
+    /**
+     * Possible default attribute values
+     *
+     * @var array
+     */
+    protected array $defaults = [];
+
     /**
      * Constructor.
      *
@@ -89,6 +96,71 @@ class ItemAttributeType implements \JsonSerializable, ArrayableInterface
         return $this->id;
     }
 
+   /**
+    * Set name
+    *
+    * @param string $name Name
+    *
+    * @return void
+    *
+    * @since 1.0.0
+    */
+    public function setName(string $name) : void
+    {
+        $this->name = $name;
+    }
+
+    /**
+     * Set l11n
+     *
+     * @param string|ItemAttributeTypeL11n $l11n Tag article l11n
+     * @param  string                      $lang Language
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setL11n($l11n, string $lang = ISO639x1Enum::_EN) : void
+    {
+        if ($l11n instanceof ItemAttributeTypeL11n) {
+            $this->l11n = $l11n;
+        } elseif ($this->l11n instanceof ItemAttributeTypeL11n && \is_string($l11n)) {
+            $this->l11n->setl11n($l11n);
+        } elseif (\is_string($l11n)) {
+            $this->l11n = new ItemAttributeTypeL11n();
+            $this->l11n->setl11n($l11n);
+            $this->l11n->setLanguage($lang);
+        }
+    }
+
+   /**
+    * Set fields
+    *
+    * @param int $fields Fields
+    *
+    * @return void
+    *
+    * @since 1.0.0
+    */
+    public function setFields(int $fields) : void
+    {
+        $this->fields = $fields;
+    }
+
+    /**
+    * Set custom
+    *
+    * @param bool $custom FieldsCustom
+    *
+    * @return void
+    *
+    * @since 1.0.0
+    */
+    public function setCustom(bool $custom) : void
+    {
+        $this->custom = $custom;
+    }
+
     /**
      * {@inheritdoc}
      */
diff --git a/Models/ItemAttributeTypeL11n.php b/Models/ItemAttributeTypeL11n.php
index 00b0884..28ff05b 100644
--- a/Models/ItemAttributeTypeL11n.php
+++ b/Models/ItemAttributeTypeL11n.php
@@ -111,6 +111,34 @@ class ItemAttributeTypeL11n implements \JsonSerializable, ArrayableInterface
         return $this->title;
     }
 
+    /**
+     * Set type.
+     *
+     * @param int $type Type id
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setType(int $type) : void
+    {
+        $this->type = $type;
+    }
+
+    /**
+     * Set language
+     *
+     * @param string $language Language
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setLanguage(string $language) : void
+    {
+        $this->language = $language;
+    }
+
     /**
      * Set title
      *
diff --git a/Models/ItemAttributeTypeMapper.php b/Models/ItemAttributeTypeMapper.php
index 212a826..1f55d2b 100644
--- a/Models/ItemAttributeTypeMapper.php
+++ b/Models/ItemAttributeTypeMapper.php
@@ -54,6 +54,12 @@ final class ItemAttributeTypeMapper extends DataMapperAbstract
             'conditional'       => true,
             'external'          => null,
         ],
+        'defaults' => [
+            'mapper'            => ItemAttributeValueMapper::class,
+            'table'             => 'itemmgmt_item_attr_default',
+            'self'              => 'itemmgmt_item_attr_default_type',
+            'external'          => 'itemmgmt_item_attr_default_value',
+        ],
     ];
 
     /**
diff --git a/Models/ItemAttributeValue.php b/Models/ItemAttributeValue.php
index 306456c..18e13aa 100644
--- a/Models/ItemAttributeValue.php
+++ b/Models/ItemAttributeValue.php
@@ -21,6 +21,8 @@ use phpOMS\Localization\ISO639x1Enum;
 /**
  * Item attribute value class.
  *
+ * The relation with the type/item is defined in the ItemAttribute class.
+ *
  * @package Modules\ItemManagement\Models
  * @license OMS License 1.0
  * @link    https://orange-management.org
@@ -111,19 +113,10 @@ class ItemAttributeValue implements \JsonSerializable, ArrayableInterface
      */
     public function __construct(int $type = 0, $value = '', string $language = ISO639x1Enum::_EN)
     {
-        $this->type = $type;
-
-        if (\is_string($value)) {
-            $this->valueStr = $value;
-        } elseif (\is_int($value)) {
-            $this->valueInt = $value;
-        } elseif (\is_float($value)) {
-            $this->valueDec = $value;
-        } elseif ($value instanceof \DateTimeInterface) {
-            $this->valueDat = $value;
-        }
-
+        $this->type     = $type;
         $this->language = $language;
+
+        $this->setValue($value);
     }
 
     /**
@@ -138,6 +131,138 @@ class ItemAttributeValue implements \JsonSerializable, ArrayableInterface
         return $this->id;
     }
 
+    /**
+     * Set value
+     *
+     * @param int|string|float $value Value
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setValue($value) : void
+    {
+        if (\is_string($value)) {
+            $this->valueStr = $value;
+        } elseif (\is_int($value)) {
+            $this->valueInt = $value;
+        } elseif (\is_float($value)) {
+            $this->valueDec = $value;
+        } elseif ($value instanceof \DateTimeInterface) {
+            $this->valueDat = $value;
+        }
+    }
+
+    /**
+     * Set value
+     *
+     * @param int $value Value
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setValueInt(int $value) : void
+    {
+        $this->valueInt = $value;
+    }
+
+    /**
+     * Set value
+     *
+     * @param string $value Value
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setValueString(string $value) : void
+    {
+        $this->valueString = $value;
+    }
+
+    /**
+     * Set value
+     *
+     * @param float $value Value
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setValueDecimal(float $value) : void
+    {
+        $this->valueDec = $value;
+    }
+
+    /**
+     * Set value
+     *
+     * @param \DateTimeInterface $value Value
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setValueDat(\DateTimeInterface $value) : void
+    {
+        $this->valueDat = $value;
+    }
+
+    /**
+     * Set default
+     *
+     * @param bool $isDefault Default
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setDefault(bool $isDefault) : void
+    {
+        $this->isDefault = $isDefault;
+    }
+
+    /**
+     * Is default value?
+     *
+     * @return  bool
+     *
+     * @since 1.0.0
+     */
+    public function isDefault() : bool
+    {
+        return $this->isDefault;
+    }
+
+    /**
+     * Set language
+     *
+     * @param string $language Language
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setLanguage(string $language) : void
+    {
+        $this->language = $language;
+    }
+
+    /**
+     * Set country
+     *
+     * @param string $country Country
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setCountry(string $country) : void
+    {
+        $this->country = $country;
+    }
+
     /**
      * {@inheritdoc}
      */
diff --git a/Models/ItemL11nType.php b/Models/ItemL11nType.php
index d29a4c8..6a8f7cf 100644
--- a/Models/ItemL11nType.php
+++ b/Models/ItemL11nType.php
@@ -35,7 +35,7 @@ class ItemL11nType implements \JsonSerializable, ArrayableInterface
     protected int $id = 0;
 
     /**
-     * Item title.
+     * Identifier for the l11n type.
      *
      * @var string
      * @since 1.0.0