Modify Tremors 2 Recoil Kit for adding realistic recoil to your AEG. For front wired M4 replicas which have a stock tube. 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 rps and under.