Amazingly realistic kickback action is easily achieved by installing Modify Tremors 2 Recoil Set. The different design of Tremors ver.2 is the separate hammer and hammer guide. This design will make the recoil impact jolt more realistic. Let you feel more powerful when you install it in the M4 Carbine.

• Recommended for 22 BPS and under.
• The hole for the stock screw on the gearbox needs to be bigger to allow new parts.