diff --git a/Models/Calendar.php b/Models/Calendar.php
index cb7840b..e35aea1 100644
--- a/Models/Calendar.php
+++ b/Models/Calendar.php
@@ -24,7 +24,7 @@ use phpOMS\Stdlib\Base\SmartDateTime;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class Calendar
+class Calendar
 {
 
     /**
diff --git a/Models/Event.php b/Models/Event.php
index 8527195..53fe0e9 100644
--- a/Models/Event.php
+++ b/Models/Event.php
@@ -26,7 +26,7 @@ use phpOMS\Stdlib\Base\Location;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class Event
+class Event
 {
 
     /**
diff --git a/Models/EventTemplate.php b/Models/EventTemplate.php
index f66e0ac..bbf9fb9 100644
--- a/Models/EventTemplate.php
+++ b/Models/EventTemplate.php
@@ -22,7 +22,7 @@ namespace Modules\Calendar\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class EventTemplate extends Event
+class EventTemplate extends Event
 {
     /**
      * Type.
diff --git a/Models/NullCalendar.php b/Models/NullCalendar.php
index faa2f9a..1d076d3 100644
--- a/Models/NullCalendar.php
+++ b/Models/NullCalendar.php
@@ -22,7 +22,7 @@ namespace Modules\Calendar\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class NullCalendar extends Calendar
+class NullCalendar extends Calendar
 {
 
 }
diff --git a/Models/NullEvent.php b/Models/NullEvent.php
index dfa9b79..89fa0d2 100644
--- a/Models/NullEvent.php
+++ b/Models/NullEvent.php
@@ -22,7 +22,7 @@ namespace Modules\Calendar\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class NullEvent extends Event
+class NullEvent extends Event
 {
 
 }
diff --git a/Models/NullSchedule.php b/Models/NullSchedule.php
index b634c08..2766a89 100644
--- a/Models/NullSchedule.php
+++ b/Models/NullSchedule.php
@@ -22,6 +22,6 @@ namespace Modules\Calendar\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class NullSchedule extends Schedule
+class NullSchedule extends Schedule
 {
 }
diff --git a/Models/Schedule.php b/Models/Schedule.php
index 843c8ec..f1363ab 100644
--- a/Models/Schedule.php
+++ b/Models/Schedule.php
@@ -24,7 +24,7 @@ use phpOMS\Stdlib\Base\Exception\InvalidEnumValue;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-final class Schedule
+class Schedule
 {
     /**
      * Schedule ID.