AR-15 Accessory: Y Caliber: 5.7X28MM Finish: Black Matte Length In INCHES: 8.0000 Threaded: Y Other FEATURES:: Medium Taper, 1:9 Twist, 4140 Chrome Moly, Salt Bath Nitride Finish, Threaded 1/2"X28" Other FEATURES2:: Radial DELAYED Blowback Bolt, Requires ENLARGED Ejection Port For Reliable Operation, Includes Bolt And Barrel
