Pro Mag 1911 Defender .45 ACP Pistol Magazine Steel Blue 7 Round COL 17-7RD. 45acp. Constructed from heat-treated blued-steel with a follower lock-plate and base-plate molded from a proprietary DuPont Zytel based black polymer; and using a spring wound from Chrome-silicon wire and heat-treated for strength and reliability. made in specialized factories Specifications for Pro Mag 1911 Defender .45 ACP Pistol Magazine: Manufacturer: ProMag Gun Make: 1911 Platform Gun Model: 1911 Defender Caliber: .45 ACP Magazine Capacity: 7 Round Color: Blue Fabric/Material: Steel Package Contents: Pro Mag 1911 Defender .45 ACP Pistol Magazine What firearm models does the manufacturer say Pro Mag 1911 Defender .45 ACP Pistol Magazine is compatible with? The manufacturer says that Pro Mag 1911 Defender .45 ACP Pistol Magazine is compatible with 1911 DefenderPro Mag COL 17-7RD: 1911 Defender .45 ACP Pistol Magazine Steel Blue 7 Round