This screw on AK-47 Krinkov style muzzle brake flash hider is designed to easily attach to the standard AK barrel 7.62X39 equipped with 14 x 1 LH thread, made from high quality heat treated steel. Muzzle brake fits AK-47 pattern rifle and pistols with 7.62mm caliber barrels. Ported on sides and top to reduces recoil, muzzle rise and flash. This AK-47 muzzle device is made specifically for AK's, it is notch for the front sight block detent pin. Finished in Military style black oxide finish. 3 inches long. One year limited warranty.