The Maglula MP5 SMG 9mm LULA Loader/Unloader fits curved 15 and 30 round 9mm MP5 SMG, HK94, and SP89 metal magazines. Avoid use on older straight magazines as loading and unloading will not be as smooth. It is simple to use in either loading or unloading mode. The loader/unloader eliminates thumb pain and wear on feed lips. It also prolongs magazine life. It is lightweight and small enough to fit in your pocket. The loader/unloader is crafted from durable reinforced polymer and is reliable in all weather.