The Maglula Loader/Unloader is simple to use in either loading or unloading mode. The loader/unloader eliminates thumb pain, wear on feed lips, and prolongs magazine life. It is crafted from durable reinforced polymer, lightweight, and is reliable in all weather. This model is compatible with Sig MPX 9mm polymer magazines. All-in-1 magazine speed loader and unloader Simple to use in either mode Eliminates thumb pain and injury Eliminates wear on feed lips Lightweight and fits in pocket