Barrel: 16" 4150CMV, chambered in 5.56 NATO, with a 1/7 twist, Socom Lightweight profile barrel and a mid-length gas system. The mid-length profile barrel is melonite QPQ, salt bath nitride coated. Barrel is finished off with a 15" 7 sided keymod free-float rail, low-profile gas block and an A2 flash hider. Upper: Forged 7075-T6 Flat top AR upper is hard coat anodized black for durability. Featuring M4 feedramp cuts, T-marks, these upper upper receivers are made for us right here in the USA. Each upper is assembled to order. Does not include BCG/CH