Magpacker Polymer AR-15 Speed Loader works with .223, 5.56 and 300 Blackout rounds in magazines of 10, 20, 30, and 40 round capacity. This Magpacker also works perfect with the Ruger Mini14 magazines up to 40 rounds and can be used with magazines that have a ranger plate. It is the smallest, smoothest, and fastest speed loader on the market. This Magpacker model quickly & easily loads most AR-15 magazines and was created to accommodate a wide range of AR-15 magazines. The Magpacker Polymer AR-15 Speed Loader still features the bullet pool area like the original Magpacker, but more compact.