The Caldwell Mag Charger Universal Pistol Loader adjustable side shims align magazines of any width for optimal use. Shims are labeled with Numbers for quick adjustment. Lock knob keeps virtually any size magazine secure.Robust polycarbonate construction for years of useErgonomic die cast aluminum handle for easy use and 'no flex' operationUniversal magazine designWorks with both single-stack and double-stack magazinesLoads 9mm, 10mm, .357, .40 and .45 cal ammoSimple to use - Just drop in a round and squeeze the leverExtremely durable polycarbonate construction