The Anderson Manufacturing Complete 7.62x39 AR-15 Bolt Carrier Group is a high-quality assembly designed to improve the performance of your AR-15 rifle. This product is built with an M16 profile and features a salt bath nitride finish that provides superior resistance against corrosion and wear. The bolt carrier is made of 8620 steel, while the bolt is constructed from 9310 steel for strength and durability. These materials and the quality of their construction make for a long-lasting and reliable product.