The FFMD 5.56 NATO 3-Port Slim Muzzle Brake is designed for AR-15 rifles with 1/2"-28 threading and .620 barrel diameter compatibility.FFMD 5.56 NATO 3-Port Muzzle BrakeSlim profile streamline design3-port configuration for effective recoil reduction.620 inch barrel diameter compatibility1/2"-28 thread pitch for standard AR-15 barrelsBlack finishSKU: FFMD556S63PSQPQEngineered to reduce muzzle rise and recoil while maintaining a low-profile appearance this muzzle brake enhances shooting accuracy and control for 5.56 NATO chambered rifles.