This is Ambi-Selector model for TM M4A1 MWS Series(which with Z-System)

Now you can change firing mode easily with your hand holding gun even if you're left-handed.Also, as it's firmly fixed, it can be used for a long time without breakage.

It replaces whole body of original selector.

Of course it includes Bolt stl too. But if only needed, please refer to the detail below.

Hex Socket Flat Head Cap Screw[M3X8] [HEAD] Diameter 6 Ø with length 2mm. [BODY] Diameter 3 Ø(2.9mm) with length 5mm.If you have any further question, please enquire toonam131@gmail.com