<p><strong>Barrel</strong>: Chrome Moly steel 16' barrel chambered in 5.56 NATO with a 1:7 twist rate, M4 barrel extension, and a carbine-length gas system. The barrel is finished off with a standard polymer handguard with heatshields, .750 F-Marked gas sight base, and an A2 flash hider.</p> <p><strong>Upper</strong>: The forged 7075-T6 A3 AR upper is machined to MIL-SPECS and hard coat anodized. It features a forged upper receiver. This upper is made for us right here in the USA by a mil-spec manufacturer.</p> <p><strong>Bolt Carrier Group</strong>: The bolt is made of shot-peened, Mil-spec Carpenter 158® steel. The gas key is secured with grade 8 fasteners and staked to the 8620 Steel Full-auto profile carrier. Includes Charging Handle.</p> <p><strong>Lower Build Kit</strong>: Includes Classic M4-Style Stock, A2 Pistol grip, Classic Lower Parts Kit, and Mil-Spec diameter 6-position buffer tube assembly. Everything you need to finish your stripped lower.</p> <p> </p>