8.5" .300 AAC BLACKOUT 1:7 NITRIDE 7" LIGHTWEIGHT M-LOK MOE+ EPT SBA3 PISTOL KITBarrel Length: 8.5"Barrel Profile: HeavyGas System: Pistol-lengthBarrel Steel: 4150V Chrome Moly VanadiumBarrel Finish: NitrideChrome Lining: NoMuzzle Thread: 5/8-24Chamber: 300AAC BlackoutTwist Rate: 1:7Barrel Extension: M4Diameter at Gas Block: .750Gas Block Type: Low-profileMuzzle Device: PSA A2 Flash HiderReceiver Material: Forged 7075 T6 AluminumReceiver Type: M4Handguard Type: PSA 7" Lightweight M-Lok RailBolt Carrier Group Included: YesBolt Steel: Carpenter 158Bolt Carrier Profile: Full-autoCharging Handle Included: YesBuild Kit: MOE+ SBA3 EPT Pistol Kit, Black