This Dirty Bird Industries Complete Upper features a Black Nitride 14.5” Sub-MOA Government Profile barrel chambered in 5.56 with a 1:7 twist. Built on a top-tier Forged Upper Receiver and finished with Dirty Bird’s 15″ SMRS V2 M-LOK Handguard. We then pinned and welded an extended flash hider to reach the a minimum barrel length of 16″, thereby reducing weight, while still retaining rigidity and performance. No corners are cut when manufacturing these complete uppers. All barrels are dimpled and cold blued, use a black nitride 4140 steel gas block and a stainless steel gas tube.