MODIFY HP-03-06
Hybrid 6.03mm Precision Inner Barrel 363 mm for M4A1 New & Old Types/R.I.S./SR16, XM177E2, SIG551)
Hybrid 6.03mm Precision Inner Barrel 363 mm for M4A1 New & Old Types/R.I.S./SR16, XM177E2, SIG551)
