Designed to deliver reliable feeding performance with your Colt®-style M4 .22LR rifle (not included), the ProMag® Colt M4 .22LR 30-Round Magazine is an affordable, yet reliable alternative to expensive factory magazines. This magazine features a DuPont® Zytel™ polymer body, delivering exceptional durability and corrosion resistance for lasting performance. A heat-treated chrome silicon wire spring and injection-molded polymer follower ensure flawless feeding. Not compatible with Ciener and G.I style .22 conversion rifles. Made in USA.