diff --git a/tests/Models/NullDepartment.php b/tests/Models/NullDepartment.php
new file mode 100644
index 0000000..d9a3736
--- /dev/null
+++ b/tests/Models/NullDepartment.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 8.0
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\Organization\tests\Models;
+
+use Modules\Organization\Models\NullDepartment;
+
+/**
+ * @internal
+ */
+final class Null extends \PHPUnit\Framework\TestCase
+{
+    /**
+     * @covers Modules\Organization\Models\NullDepartment
+     * @group framework
+     */
+    public function testNull() : void
+    {
+        self::assertInstanceOf('\Modules\Organization\Models\Department', new NullDepartment());
+    }
+
+    /**
+     * @covers Modules\Organization\Models\NullDepartment
+     * @group framework
+     */
+    public function testId() : void
+    {
+        $null = new NullDepartment(2);
+        self::assertEquals(2, $null->getId());
+    }
+}
diff --git a/tests/Models/NullPosition.php b/tests/Models/NullPosition.php
new file mode 100644
index 0000000..851050a
--- /dev/null
+++ b/tests/Models/NullPosition.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 8.0
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\Organization\tests\Models;
+
+use Modules\Organization\Models\NullPosition;
+
+/**
+ * @internal
+ */
+final class Null extends \PHPUnit\Framework\TestCase
+{
+    /**
+     * @covers Modules\Organization\Models\NullPosition
+     * @group framework
+     */
+    public function testNull() : void
+    {
+        self::assertInstanceOf('\Modules\Organization\Models\Position', new NullPosition());
+    }
+
+    /**
+     * @covers Modules\Organization\Models\NullPosition
+     * @group framework
+     */
+    public function testId() : void
+    {
+        $null = new NullPosition(2);
+        self::assertEquals(2, $null->getId());
+    }
+}
diff --git a/tests/Models/NullUnit.php b/tests/Models/NullUnit.php
new file mode 100644
index 0000000..d18320b
--- /dev/null
+++ b/tests/Models/NullUnit.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 8.0
+ *
+ * @package   tests
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\Organization\tests\Models;
+
+use Modules\Organization\Models\NullUnit;
+
+/**
+ * @internal
+ */
+final class Null extends \PHPUnit\Framework\TestCase
+{
+    /**
+     * @covers Modules\Organization\Models\NullUnit
+     * @group framework
+     */
+    public function testNull() : void
+    {
+        self::assertInstanceOf('\Modules\Organization\Models\Unit', new NullUnit());
+    }
+
+    /**
+     * @covers Modules\Organization\Models\NullUnit
+     * @group framework
+     */
+    public function testId() : void
+    {
+        $null = new NullUnit(2);
+        self::assertEquals(2, $null->getId());
+    }
+}