Slim 5.56 NATO 3-Port Muzzle Brake .620 1/2"-28 Threads Black - a precision muzzle brake chambered for 5.56 that redirects propellant gases to counter recoil and muzzle rise, keeping your sights on target for faster, flatter follow-up shots. Features: Reduces felt recoil and muzzle climb 3-Port design 1/2"-28 threads Verify thread pitch matches your barrel before installation