Barrel: 7.5" Nitride Chrome-Moly Vanadium Barrel Chambered in 5.56 NATO, with a 1:7 twist rate, M4 barrel extension, and a pistol-length gas system. This nitride barrel is finished off with a PSA 7" Lightweight M-Lok free-float rail, .750" diameter low profile gas block, and an A2 flash hider. Upper: Forged 7075-T6 A3 AR upper is made to MIL-SPECS and hard coat anodized black for durability. These uppers are made for us right here in the USA by a mil-spec manufacturer. *Bolt Carrier Group and Charging Handle Not Included