Barrel: 7" Nitride treated barrel for durability and chambered in 300AAC Blackout. Pistol length gas barrel is finished off with a Magpul MOE M-Lok carbine length handguard, a low profile gas block, and a patent-pending PSA muzzle device designed to hold the handguard endcap in place. 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: Full-auto profile bolt carrier group. Shot-peened, mil-spec Carpenter No. 158? steel bolt. Gas Key Hardened to USGI Specifications, Fastened with Grade 8 screws, and Staked Per Mil-Spec. 8620 steel M-16 profile carrier is chrome-lined and phosphate coated. Lower: These forged lowers are quality made using 7075-T6 aluminum and are marked "MULTI" for caliber. The finish is hard coat anodized. The pistol is finished with Magpul MOE Grip, MOE Trigger Guard, and H&R HAR-15 Adjustable Pistol Stabilizing Blade.