diff --git a/src/pocketmine/network/mcpe/protocol/types/WindowTypes.php b/src/pocketmine/network/mcpe/protocol/types/WindowTypes.php
index afa36f5a9..6394e76ea 100644
--- a/src/pocketmine/network/mcpe/protocol/types/WindowTypes.php
+++ b/src/pocketmine/network/mcpe/protocol/types/WindowTypes.php
@@ -46,7 +46,8 @@ interface WindowTypes{
 	public const TRADING = 15;
 	public const COMMAND_BLOCK = 16;
 	public const JUKEBOX = 17;
-
+	public const ARMOR = 18;
+	public const HAND = 19;
 	public const COMPOUND_CREATOR = 20;
 	public const ELEMENT_CONSTRUCTOR = 21;
 	public const MATERIAL_REDUCER = 22;