Chamber: 223 Wylde for 5.56 NATO. Barrel: 13.9″, 14.5″, 16″, mid-length gas system. Pinned and welded muzzle device to exceed 16.0″ total overall length as needed. Heavy-profile 416-R stainless steel gun-drilled and reamed in 5R rifling and 1:8 twist. Stress relieved, precision air-gauged. Dual Taper Lock (DTL) system secures and centers the barrel. Quantum-series lower receivers use patented Presslock technology with linear compression pad for a tight, rattle free fitment, no carrier tilt. Handguard: 7-side M-LOK compatible. Stryker ambidextrous charging handle. Weight: 6.875 lbs. Black anodized is standard receiver color; several other colors are $50-$75 upcharges. Many options for gas block, charging handle, triggers, etc. 300 BLK added 2023. 6 ARC added 2024. Made in Chandler, Ariz.