Advantage Arms is excited to offer their high quality .22 Long Rifle conversion kit magazine for Glock G20 and G21 firearms. This magazine is made from a durable polymer, features a 10 round capacity, and is designed to be used in conjunction with an Advantage Arms Glock 20/21 rimfire conversion kit. It also features a last round hold open. This is the perfect option for shooters who want to train at the range with their carry/duty pistols, but also want to save money on ammunition. It requires an Advantage Arms Conversion Slide Kit (not included).