These compensators are specifically designed for the XD/XDM to work with .40 caliber ammuntion and a reduced power recoil spring. Anodized 6061 aluminum for a light weight, long lasting compensator to tame muzzle flip and soften recoil. 9/16x24 tpi requires .4" to .5" of threads for .40 S&W. Not for factory threaded barrels  1.13 oz