CMMG ZEROED .308WIN Bolt Catch Black. The ZEROED AR10 extended bolt catch features dual oversized extended paddles with a tactile machined surface. Steel construction with a durable finish makes for a robustly built component with excellent ergonomics for confident bolt catch operation every time. Specifications for CMMG ZEROED .308Win Bolt Catch: Manufacturer: CMMG Gun Model: AR-10 Fabric/Material: Steel Caliber: .308 Winchester Color: Black Finish: Durable Condition: New Package Contents: CMMG ZEROED .308Win Bolt Catch What firearm models does the manufacturer say CMMG ZEROED .308Win Bolt Catch is compatible with? The manufacturer suggests that CMMG ZEROED .308Win Bolt Catch is compatible with AR-10CMMG 38CA5C3: ZEROED .308WIN Bolt Catch Black