PSA 16" MID-LENGTH 5.56 NATO 1/7 NITRIDE MOE EPTUPPER ONLY WITH BCG N CHARGING HANDELBarrel Length: 16"Gas System: Mid-LengthBarrel Profile: A2Barrel Steel: Chrome MolyBarrel Finish: NitrideChrome Lining: noneMuzzle Thread: 1/2-28Chamber: 5.56 NATOTwist Rate: 1 in 7"Barrel Extension: M4Diameter at Gas Block: .750"Gas Block Type: F-marked Front Sight BaseMuzzle Device: A2 Flash HiderReceiver Material: Forged 7075 T6Receiver Type: M4Bolt Carrier Group Included: YesBolt Steel: Carpenter 158Bolt Carrier Profile: Full-autoCharging Handle Included: Yes