Stern Defense Shock Proof Bolt Catch Black SDSPBoltCatchD. Introducing our new Shock Proof bolt catch. Made with S7 Steel. Our bolt catch utilizes superior materials and testing to provide unparalleled life and reliability. In testing our product handled more than 63x the punishment of our mil-spec competitors. Spring plunger and detent not included by default Specifications for Stern Defense Shock Proof Bolt Catch: Manufacturer: Stern Defense Color: Black Package Contents: Stern Defense Shock Proof Bolt Catch Stern Defense SDSPBoltCatchD: Shock Proof Bolt Catch Black