This UTG PRO® high-quality steel AR-15 stubby 9mm muzzle brake device with crush washer has 1/2x28 UNEF threads. This 9mm AR muzzle brake 1/2x28 compensator features gas dispersion porting to reduce felt recoil and muzzle rise. This 9mm muzzle device is made from high-quality steel with a black military type nitride coating and is 1.75 inches long for 9mm caliber AR platform rifles and pistols. It is proudly made in the USA with a UTG PRO lifetime warranty.