The American Precision Arms Gen 4 Fat Bastard Muzzle Brake for 30 Caliber rifles features advanced tunable top ports for unmatched shooting stability. Through meticulous testing of port size and positioning this muzzle brake eliminates vertical movement providing an exceptionally flat shooting experience. Finished in durable nitride it offers a reliable and robust construction. The brake is designed with a 5/8"x24 thread pattern ensuring compatibility with a wide range of firearms. Experience superior performance and precision with this innovative muzzle brake.