FNX-45 STD Barrel BLK. Replace your worn factory part or keep one as a backup. FN America factory parts are made with the same quality in materials and workmanship that you have come to expect and trust from FN America. SpecificationsCaliber: .45 ACPLength: 4.5"Twist: 1:16 RHStainless Steel ConstructionPolished chamber and feed ramp FN America FNX-45 Standard Barrel Black 67206-9