ProMag 1911 Government Model .45 ACP Pistol Magazine 15 Round Blued 1 Pack Steel 15RD. It is constructed of heat treated steel with injection molded mag follower and mag spring formed from chrome silicone wire. Specifications for ProMag 1911 Government Model .45 ACP 15 Round Pistol Magazine: Manufacturer: ProMag Gun Make: 1911 Platform Gun Model: Colt 1911 Government 5in Caliber: .45 ACP Magazine Capacity: 15 Round Color: Blued Condition: New Fabric/Material: Steel Features of Pro Mag 1911 Government Model .45 ACP 15-Round Pistol Magazine Magazine body constructed of heat treated steel with black oxide finish Injection molded magazine follower Magazine spring formed from heat treated chrome silicone wire Package Contents: ProMag 1911 Government Model .45 ACP 15 Round Pistol Magazine What firearm models does the manufacturer say ProMag 1911 Government Model .45 ACP 15 Round Pistol Magazine is compatible with? The manufacturer says that ProMag 1911 Government Model .45 ACP 15 Round Pistol Magazine is compatible with Colt 1911 Government 5inProMag COL-A5-15RD: 1911 Government Model .45 ACP Pistol Magazine 15 Round Blued 1 Pack Steel