diff --git a/Models/Balance.php b/Models/Balance.php
index 8b66c65..32e8969 100644
--- a/Models/Balance.php
+++ b/Models/Balance.php
@@ -24,7 +24,7 @@ use phpOMS\Utils\IO\ExchangeInterface;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Balance
+final class Balance
 {
 
     /**
diff --git a/Models/BatchPosting.php b/Models/BatchPosting.php
index 13df748..895b8f5 100644
--- a/Models/BatchPosting.php
+++ b/Models/BatchPosting.php
@@ -22,7 +22,7 @@ namespace Modules\Accounting\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class BatchPosting implements \Countable
+final class BatchPosting implements \Countable
 {
 
     /**
diff --git a/Models/Creditor.php b/Models/Creditor.php
index 00bdf1a..96dc403 100644
--- a/Models/Creditor.php
+++ b/Models/Creditor.php
@@ -22,7 +22,7 @@ namespace Modules\Accounting\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Creditor
+final class Creditor
 {
 
     /**
diff --git a/Models/Debitor.php b/Models/Debitor.php
index 7f27583..429b4f3 100644
--- a/Models/Debitor.php
+++ b/Models/Debitor.php
@@ -22,7 +22,7 @@ namespace Modules\Accounting\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class Debitor
+final class Debitor
 {
 
     /**
diff --git a/Models/ImpersonalAccount.php b/Models/ImpersonalAccount.php
index 3076193..c87f378 100644
--- a/Models/ImpersonalAccount.php
+++ b/Models/ImpersonalAccount.php
@@ -24,7 +24,7 @@ use phpOMS\Utils\IO\ExchangeInterface;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ImpersonalAccount
+final class ImpersonalAccount
 {
 
     /**
diff --git a/Models/IncomeStatement.php b/Models/IncomeStatement.php
index 0166ab0..ab784b3 100644
--- a/Models/IncomeStatement.php
+++ b/Models/IncomeStatement.php
@@ -22,7 +22,7 @@ namespace Modules\Accounting\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class IncomeStatement
+final class IncomeStatement
 {
     private $id = 0;
 
diff --git a/Models/InvoicePosting.php b/Models/InvoicePosting.php
index 416e9ce..8791d30 100644
--- a/Models/InvoicePosting.php
+++ b/Models/InvoicePosting.php
@@ -22,7 +22,7 @@ namespace Modules\Accounting\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class InvoicePosting extends PostingAbstract
+final class InvoicePosting extends PostingAbstract
 {
 
     /**