diff --git a/Controller/BackendController.php b/Controller/BackendController.php
index c6b107a..fef0583 100644
--- a/Controller/BackendController.php
+++ b/Controller/BackendController.php
@@ -33,7 +33,7 @@ use phpOMS\Views\View;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class BackendController extends Controller
+final class BackendController extends Controller
 {
     /**
      * @param RequestAbstract  $request  Request
diff --git a/Models/Client.php b/Models/Client.php
index efe9b7c..6908794 100644
--- a/Models/Client.php
+++ b/Models/Client.php
@@ -25,7 +25,7 @@ use Modules\Profile\Models\Profile;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Client
+final class Client
 {
     private $id = 0;
 
diff --git a/Models/ClientMapper.php b/Models/ClientMapper.php
index 319fb11..975cf64 100644
--- a/Models/ClientMapper.php
+++ b/Models/ClientMapper.php
@@ -24,7 +24,7 @@ use phpOMS\DataStorage\Database\Query\Builder;
 use phpOMS\DataStorage\Database\Query\Column;
 use phpOMS\DataStorage\Database\RelationType;
 
-class ClientMapper extends DataMapperAbstract
+final class ClientMapper extends DataMapperAbstract
 {
     /**
      * Columns.