Crafted to meet the highest standards ProMag presents the ultimate addition to your FN 509 9mm pistol: a 50-round drum magazine a perfect companion for extended shooting sessions.Not just about the capacity ProMag ensures that the quality is top-notch by utilizing advanced materials in its construction.DuPont Zytel-based polymer housingBlue steel upper magazine towerHeat-treated stainless steel springEnsuring longevity and reliability the drum magazine's spring is meticulously formed from heat-treated stainless steel. To further boost its durability an injection-molded magazine follower is integrated.Whether you're on the range or engaged in tactical training this ProMag FN 509 drum magazine promises consistency robustness and an unparalleled shooting experience.Enhance your firepower and trust in the ProMag name.Score big savings and fast shipping when you shop our large selection of 9mm ammo in bulk available online at Ammunition Depot.Searching for new range gear? Enjoy big savings and fast shipping on our collection of Backpacks Range Bags Gun Cases and Sling Bags available online from the brands you know and trust at Ammunition Depot.