diff --git a/docs/en/Object-Extensions.md b/docs/en/Object-Extensions.md
index 4c2b1b5454..bc4fc911c4 100644
--- a/docs/en/Object-Extensions.md
+++ b/docs/en/Object-Extensions.md
@@ -9,10 +9,10 @@ ABP Framework provides an **object extension system** to allow you to **add extr
 This is the interface to make a class extensible. It simply defines a `Dictionary` property:
 
 ````csharp
-Dictionary<string, object> ExtraProperties { get; }
+ExtraPropertyDictionary ExtraProperties { get; }
 ````
 
-Then you can add or get extra properties using this dictionary.
+`ExtraPropertyDictionary` class is inherited from the `Dictionary<string, object>` class. You can add or get extra properties using this dictionary.
 
 ### Base Classes
 
@@ -413,4 +413,4 @@ See the [Entity Framework Core Integration document](Entity-Framework-Core.md) f
 
 ## See Also
 
-* [Module Entity Extensions](Module-Entity-Extensions.md)
\ No newline at end of file
+* [Module Entity Extensions](Module-Entity-Extensions.md)