Exceptionally rugged, combat- and competition-ready magazine functions flawlessly, even when left fully loaded for extended periods. Corrosion-proof, self-lubricating one-piece body of fiber-reinforced, molded polymer has no spot welds or joints to impair the follower, and the constant internal curve ensures smooth, unobstructed movement of the round stack. Anti-tilt follower stabilizes the stack to help prevent nose-diving and bolt-over-head failures. Heat-treated, stainless steel spring is stress-relieved for optimal performance. Withstands the heat from prolonged full-auto fire and is not harmed by most bore cleaners and solvents. Exterior ribbing provides added gripping surface; magaz Mfg: Brownells