diff --git a/Models/MediaMapper.php b/Models/MediaMapper.php
index 78e3305..8c0724d 100644
--- a/Models/MediaMapper.php
+++ b/Models/MediaMapper.php
@@ -49,6 +49,12 @@ class MediaMapper extends DataMapperAbstract
      */
     protected static $table = 'media';
 
+    /**
+     * Created at.
+     *
+     * @var string
+     * @since 1.0.0
+     */
     protected static $createdAt = 'media_created_at';
 
     /**