ProMag magazines are built for strength and reliability, featuring high carbon, heat-treated steel bodies that are TIG-welded for maximum durability. The precision wound springs, made from heat-treated chrome silicon wire, ensure consistent feeding, while the injection molded polymer bases and followers provide long lasting performance. This combination of quality materials and expert craftsmanship guarantees a magazine that delivers dependable function shot after shot. Magazine with a 18-round capacity Designed to fit Colt 1911 9mm pistol The magazine body is constructed from heat-treated steel with a durable black-oxide finish Precision-molded for smooth, reliable feeding, reducing friction and ensuring consistent round stacking The magazine spring is formed from heat-treated chrome silicone wire Proudly made in the USA for superior quality and craftsmanship