DoubleStar AR-15 Standard Bolt Carrier Group With O-Ring AR100

DoubleStar - AR-15 Bolt Carrier Group Complete bolt-and-carrier group easily drops into a standard Mil-Spec AR-15 upper and it s ready to shoot. The bolt assembly contains the correct black insert and tool steel extractor. The bolt is MPI (Magnetic Particle Inspected) and HPT (High Pressure Tested) material batch tested to ensure high quality and longevity. Bolt and carrier feature a matte black phosphate finish that resists heat wear and corrosion. Carrier is chrome lined and has a staked gas key attached. Features and Specifications: Manufacturer Number: AR100 Made from Carpenter 158 steel Batch MPI and HPT tested bolt Matte black phosphate finish bolt and carrier Chrome lined Carrier with staked gas key attached Includes: Bolt assembly Firing pin Firing pin Retaining pin Cam pin Complete carrier