PW9 AR Pistol Caliber Firing Pin And Spring Black. Specifications for PW9 AR Pistol Caliber Firing Pin And Spring: Manufacturer: PW9 Color: Black Finish: Nitride Fabric/Material: 4140 Steel Caliber: 9mm Luger .40 S&W .45 ACP 10mm Auto Gun Make: AR Platform Gun Model: Universal Features of PW9 AR Pistol Caliber Firing Pin And Spring PCC Compatible Package Contents: PW9 AR Pistol Caliber Firing Pin And Spring Hardware What firearm models does the manufacturer say PW9 AR Pistol Caliber Firing Pin And Spring is compatible with? The manufacturer says that PW9 AR Pistol Caliber Firing Pin And Spring is compatible with UniversalPW9 PW98292B4: AR Pistol Caliber Firing Pin And Spring Black