Key Facts:
Compatible with M4 Retractable Stock
HP-01-01 TREMORS Recoil System for M4 Carbine
Details:
Includes: Recoil Action/ Recoil Spring Guide/ Primary Screw/ Secondary Screw
The recoil impact jolt is realistic. You can feel the difference in the first time you shoot it.
This Version is for Front Wired M4
TREMORS M4 Recoil Action Instruction Manual
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