Brownells M16 Mil-Spec MP Bolt Carrier Group Black Phosphate

Complete M16 Bolt Carrier Group: Fully assembled Bolt Carrier Group; including the bolt, bolt carrier, gas key, firing pin, cam pin, and firing pin retaining pin Every Bolt is Magnetic Particle Inspected (MPI) The Bolt is machined from Carpenter 158 steel Following machining, the Bolt is heat treated and shot peened Installed extractor includes red o-ring with spring M16 Bolt Carrier is machined from 8620 steel and hardened Interior of Bolt Carrier Carrier Key & Bolt Carrier are chrome lined on the M16 Phosphate Bolt Carrier Group only M16 Bolt Carrier will function in semi-auto or full-auto AR-15/M16 Gas Key Screws are properly Mfg: Brownells SPECS: Bolt - Carpenter 158 steel, Magnetic Particle Inspected, High Pressure Tested. Carrier - 8620 hardened steel, M16. Matte black phosphate finish.