PDI 01 6.01mm Precision Inner Barrel for Marui M4A1/S (375mm)

PDI 01 6.01mm Precision Inner Barrel for Marui M4A1/S (375mm) Internal diameter 6.01mm built for precision shooting Genuine Products by PDI Stainless Steel Tightbore Upgrade Barrel Advance Technology forming by Cold Forging on Stainless Steel result in tolerance no more than Suitable For Tokyo Marui M4A1 Series Airsoft Gas Blow Back GBB Rifle