Enhanced 9mm Blowback AR-9 Bolt Carrier Group is compatible with both COLT and GLOCK magazine configurations. Features reliable AR-15 style extractor claw with O-Ring and spring and broad trigger compatibility with ramped bottom geometry. Charging handle interfaces directly on bolt carrier surface that can withstand vigorous pulling force without the worry of shearing off the carrier key. Reinforced firing pin is held in place with standard firing pin cotter pin. Features : 9mm Blowback AR-9 Bolt Carrier Group GLOCK and COLT Magazine Compatible MilSpec 8620 Heat Treated Steel Carrier Reliable External AR-15 Style Extractor Full-Auto Compatible Compatible with Most AR-15 Triggers Durable Hard Nitride Black Finish Removable Carrier Weight Compatible with Dust Cover