The Caldwell Mag Charger Universal Pistol Loader makes hand loading pistol magazines two times faster! The Universal Pistol Loader works with both single-stack and double-stack magazines. It loads 9mm, 10mm, .357, .40cal and.45 cal ammo. All you have to do is drop in a round and squeeze the lever. The adjustable side shims align magazines of any width for optimal use. The shims are labeled with numbers for quick adjustment. The lock knob keeps virtually any size magazine secure and the robust poly-carbonate construction will hold up for years of use!