Barrel: Chrome-moly vanadium steel barrel nitrided and chambered in 5.56 NATO with a 1:7 twist rate M4 barrel extension and a mid-length gas system. This A2 profile barrel is finished off with a 13.5" DPMS M-Lok free-float handguard low-profile gas block and A2 flash hider.Upper: Forged 7075-T6 A3 AR upper is machined to MIL-SPECS and hard coat anodized. Uppers include forward assist and dust cover. These uppers are made for us right here in the USA by a mil-spec manufacturer.Bolt Carrier Group: Full-auto profile bolt carrier group. Shot-peened mil-spec Carpenter 158 steel bolt. Gas Key Hardened to USGI Specifications fastened with Grade 8 screws and Staked Per Mil-Spec. Carrier is 8620 steel M-16 full-auto profile.Lower: These forged lowers are quality made using 7075-T6 aluminum and are marked "MULTI" for the caliber. Finish is hard-coat anodized. The Mil-spec diameter 7075-T6 buffer tube is hard-coat anodized with 6 adjustment positions and is fitted with a B5 Bravo Stock B5 premium grip B5 trigger guard and Panther Polished Trigger (PPT). Caliber: 5.56 NATO Barrel Length: 16 inches Barrel Profile: M4 Barrel Steel: Chrome Moly Vanadium Barrel Finish: Nitride Chrome Lining: No Muzzle Thread Pattern: 1/2" x 28 Twist Rate: 1 in 8" Barrel Extension: M4 Gas System Length: Carbine Diameter at Gas Block: .750" Gas Block Type: F-marked Front Sight Base Muzzle Device: A2 -style Receiver Material: Forged 7075-T6 Receiver Type: M4 Handguard Type: M4 with heat shields Bolt Material: Carpenter 158 Steel Bolt Carrier Profile: Full Auto Fire Control Group: Panther Polished Trigger (PPT) Grip: B5 Premium Grip Stock: B5 Bravo Buffer Tube Length: Carbine Buffer Tube Diameter: Mil-spec Overall Length: 32 inches Weight (as configured): 6.8 lbs