Fits AR-15 rifles with 1/2x28 threads. The muzzle brake ports greatly reduce recoil impulse and muzzle rise. Pilot holes are included for muzzle brake tuning and to pin-and-weld on short-barreled rifles. A black melonite coating provides maximum protection against harsh environmental conditions. Precision machined from US mill-certified steel bar stock. Installation requires no permanent modifications. MADE IN THE U.S.A.