diff --git a/Models/DepartmentMapper.php b/Models/DepartmentMapper.php
index 47da65a..dad25d3 100644
--- a/Models/DepartmentMapper.php
+++ b/Models/DepartmentMapper.php
@@ -59,6 +59,14 @@ final class DepartmentMapper extends DataMapperAbstract
         ],
     ];
 
+    /**
+     * Model to use by the mapper.
+     *
+     * @var string
+     * @since 1.0.0
+     */
+    protected static string $model = Department::class;
+
     /**
      * Primary table.
      *
diff --git a/Models/PositionMapper.php b/Models/PositionMapper.php
index 28f9e56..21d9b0d 100644
--- a/Models/PositionMapper.php
+++ b/Models/PositionMapper.php
@@ -59,6 +59,14 @@ final class PositionMapper extends DataMapperAbstract
         ],
     ];
 
+    /**
+     * Model to use by the mapper.
+     *
+     * @var string
+     * @since 1.0.0
+     */
+    protected static string $model = Position::class;
+
     /**
      * Primary table.
      *
diff --git a/Models/UnitMapper.php b/Models/UnitMapper.php
index 8d15685..1b402d9 100644
--- a/Models/UnitMapper.php
+++ b/Models/UnitMapper.php
@@ -54,6 +54,14 @@ final class UnitMapper extends DataMapperAbstract
         ],
     ];
 
+    /**
+     * Model to use by the mapper.
+     *
+     * @var string
+     * @since 1.0.0
+     */
+    protected static string $model = Unit::class;
+
     /**
      * Primary table.
      *