Description Modify Tremors 2 Recoil System for M4 AEGs Features: – Patent No. M374045 – Compatible with M4 Retractable Stock – For Front Wired M4 Airsoft AEG only – The recoil impact jolt is realistic. You can feel the difference in the first time you shoot it. – Includes: Recoil Action/ Recoil Spring Guide/ Primary Screw/ Secondary Screw TREMORS M4 Recoil Action Instruction Manual
