The Maglula Magazine Loader and Unloader is simple and easy to use. It fits Sig MPX SMG 9mm magazines, version one and two, and has been tested and combat proven. The MPX Loader is reliable in all weather conditions and prolongs the life of your magazines. This loader eliminates wear on feed lips as well as thumb pain and injuries. If your looking to reload your magazine fast at the range, look no further, the Loader for the Sig MPX is an excellent choice.