Dark Storm Industries Ambidextrous Bolt Catch Black. Machined from durable steel and finished in black it ensures consistent bolt hold-open and release performance during reloads from either side. Specifications for Dark Storm Industries Ambidextrous Bolt Catch: Manufacturer: Dark Storm Industries Gun Model: AR-15 Fabric/Material: Steel Color: Black Gun Make: AR Platform Gun Type: Rifle Features of Dark Storm Industries Ambidextrous Bolt Catch Lower receiver will require modification (gunsmith recommended) Black finish for corrosion resistance Spring detent and roll pin not included Package Contents: Dark Storm Industries Ambidextrous Bolt Catch What firearm models does the manufacturer say Dark Storm Industries Ambidextrous Bolt Catch is compatible with? The manufacturer suggests that Dark Storm Industries Ambidextrous Bolt Catch is compatible with AR-15Dark Storm Industries DSI-LWR-BLTC5-AMBI: Ambidextrous Bolt Catch Black