To fully maximize the usage of your Cry Havoc Tactical QRB (Quick Release Barrel) kit for the AR 308 they offer these additional 308 Barrel Locking Plate Kits to allow you to swap different barrels on a single lower. What to switch up between a .308 16″ barrel and a .308 20″ barrel in seconds while holding within 1 MOA? This kit makes that happen. The 308 QRB Kit can only be used on Barrels with a maximum outside diameter of 1.200″” and Free Float Hand Guards with a maximum width of 2.2″” Also the QRB will add 1.5″” to the length of your free-floating hand guard. To purchase the proper kit simply selection the gas tube option that matc Mfg: Cry Havoc Tactical Inc.