The Rosco Bloodline Sauce Pack AR-15 Firearm Parts includes a 16 inch 5.56 NATO barrel, bolt carrier group, gas block, and gas tube. Barrel is made from 41V50 chrome moly vanadium steel with a black nitride finish. Mid-length gas system, low-profile gas block, and Melonite-coated BCG and gas tube. All components manufactured in the USA for reliable AR-15 builds.