50-round drum Magazine Fits most AR-308 / .308 Cal AR type rifles using LR-308 (DPMS) or SR-25 pattern magazines Over molded stamped steel feed lips and magazine catch Magazine body constructed of a proprietary DuPont Zytel based polymer Injection molded magazine follower Heat treated stainless steel magazine spring Patented Design Does not fit rifles using Armalite pattern magazines Made in USA Mfg: Pro Mag