Microbest 5.56 NATO AR-15 Bolt Carrier Group Black Nitride

Microbest 5.56 NATO AR 15 Bolt Carrier Group - Black Nitride The Microbest 5.56 NATO AR-15 Bolt Carrier is known for being the benchmark for quality and reliability throughout the industry. Microbest not only manufactures its bolt carriers but also provides parts to some of the biggest and most well-known brands. These AR-15 bolt carriers feature a corrosion-resistant salt bath nitride finish and are backed by a lifetime warranty. Features .233/5.56 NATO Corrosion-resistant salt bath nitride finish M16 cut Aircraft-quality 8620 steel carrier 4130 steel gas key Properly staked grade 8 gas key screws Carpenter 158 steel bolt 4140 steel extractor MIL-SPEC O-ring MIL-SPEC gas rings 4140 steel cam pin 8740 steel firing pin with hard chrome finish Magnetic particle inspected Lifetime warranty Proudly made in the U.S.A.