Barrel: 7.5" 4150V Chrome Moly Vanadium steel, phosphate coated and chambered in 5.56 NATO  with a 1 in 7" twist. Pistol-length gas barrel is finished off with a PSA 7" Lightweight M-Lok Rail, a 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. Featuring a mil-spec finish, these uppers are made for us right here in the USA by a mil-spec manufacturer. Bolt: Bolt is made of Mil-spec shot-peened Carpenter 158 steel. Gas key is secured with grade 8 fasteners and staked per mil-spec. #html-body [data-pb-style="62DF82896312E"]{justify-content: flex-start; display: flex; flex-direction: column; background-position: left top; background-size: cover; background-repeat: no-repeat; background-attachment: scroll; border-style: none; border-width: 1px; border-radius: 0px; margin: 0px 0px 10px; padding: 10px;}#html-body [data-pb-style="62DF82896313C"]{border-style: none; border-width: 1px; border-radius: 0px; margin: 0px; padding: 0px;}