The ProMag Pro Cola30 Mag 22LR 30rd is a durable high-performance magazine designed specifically for your Colt M4. Constructed from tough DuPont Zytel polymer it features an injection molded mag follower and a mag spring made from resilient chrome silicone wire for reliable feeding. With a sleek black finish and a 30-round capacity this detachable magazine is perfect for extended range sessions. Proudly made in the USA it ensures top-notch quality and fit. Note: Not compatible with Ciener and G.I. style .22 conversion rifles.