Tacfire's combo wrench serves both the 5.56 and .308 AR platforms in one easy to use tool. This wrench aids in the assembly, tightening or removal of barrel nuts, muzzle brakes, barrel extensions, castle nuts, delta ring assemblies and hex bolts/screws. Uniquely designed, it offers extreme versatility as it features the ability to build, service and maintain both your 5.56 AR-15 and .308 AR-10 rifles. The wrench includes the following features: .223/5.56 Barrel nut, 1 1/6" NSR barrel nut, .223/5.56 Free float barrel nut, .308 Free Float barrel Nut, 3/4" Muzzle brake, .223/5.56 Barrel extension, .308 Barrel extension, Castle nut wrench, AR-15 Delta ring assembly removal tool, 1/4" Hex, 7/16" Hex, 1/4" Driver and 1/2" Driver.