This 40-round drum magazine from ProMag is compatible with 1911 Government Model 45 ACP pistols.The drum housing is constructed of a proprietary DuPont Zytel-based polymer with a blue steel upper magazine tower. The magazine's spring is formed from heat-treated stainless steel wire and has an injection-molded magazine follower.ProMag1911 Gov Model45 ACP Drum Magazine40 Round CapacityFits 1911 Government Model 45 ACP PistolOrder your ProMag 1911 drum magazine online today!Searching for 45 ACP Ammo? Score big savings when you shop our large selection of cheap 45 ACP ammo for sale.