ProMag magazines represent the pinnacle of engineering, combining time-honored techniques like traditional stamping and welding of heat-treated high carbon steel with advanced precision injection molding using Mil-Spec polymer compounds. Each ProMag magazine is backed by a lifetime guarantee against manufacturer's defects, ensuring unparalleled reliability. The ProMag drum magazine is crafted from DuPont Zytel-based polymer, with its upper tower featuring a full-length steel internal insert meticulously stamped and welded to match the high standards of factory magazines. This construction guarantees robustness and precision, making it an essential choice for serious shooters and enthusiasts alike.