Rise Armament AR-15 Bolt Carrier Group - Black Nitride - The Rise Armament AR-15 Bolt Carrier Group (BCG) manufactured with precision and individually inspected to ensure high-level performance. The easy-to-clean black nitride finish offers unmatched strength with each pull of the trigger. The RISE AR-15 BCG, both the black nitride and nickel boron models, offer a full-auto profile and are compatible with forced reset safety selectors. A nickel boron bolt carrier group is also available. Features Made in the USA ; High-strength and easy-to-clean black nitride finish; Features a full-auto profile for compatibility with forced reset selectors and forced reset triggers; Individually MPI tested; Bolt: 9310 MPI tested; Carrier: 8620 tool steel heat treated and case hardened; Gas key: tool steel - grade 8 hardened fasteners and staked properly; Cam pin: 4140 steel; Extractor: tool steel - shot peened;