The ProMag Industries DRM-A84 50-Round Drum Magazine enhances your FN 509 9MM Pistol experience with unmatched reliability and durability. Engineered for optimal performance, this magazine features a robust steel construction and is guaranteed to withstand rigorous conditions. Enjoy peace of mind with a product that is proudly made in the USA and supported by a lifetime warranty against manufacturer defects. 50-Round Drum Magazine Fits FN 509 9MM Pistol Magazine Body Constructed of Heat Treated Steel with Black Oxide Finish Injection Molded Magazine Follower Magazine Spring Formed From Heat Treated Chrome Silicon Wire Made in the U.S.A. Trust ProMag for exceptional performance at the range or in critical situations.