ProMag FN FNX Pistol Magazine .45 ACP 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 FN FNX .45 ACP 15 Round Pistol Magazine: Manufacturer: ProMag Gun Make: FN Herstal Gun Model: FN FNX-45 Caliber: .45 ACP Magazine Capacity: 15 Round Color: Blued Fabric/Material: Polymer Package Contents: ProMag FN FNX .45 ACP 15 Round Pistol Magazine What firearm models does the manufacturer say ProMag FN FNX .45 ACP 15 Round Pistol Magazine is compatible with? The manufacturer suggests that ProMag FN FNX .45 ACP 15 Round Pistol Magazine is compatible with FN FNX-45ProMag FNH-A5-15RD: FN FNX Pistol Magazine .45 ACP 15 Round Blued 1 Pack Steel