This is the Zeagle Sternum Strap Assembly for BCD Buckling Strap Scuba Diving BC&';s Features: Fits Zeagle BCD&';s Easy to install Adds stability to BCD/cylinder system For increased comfort Squeeze-style side-release adjustable buckle If your BCD currently lacks a sternum strap and you want the benefit of using one, or you want a spare backup strap, then this easy to install strap assembly is what you&';re looking for. A sternum strap increases the stability of your BCD/cylinder system by preventing the shifting of the BCD when you&';re swimming on your side or turning on a dive. It also keeps the shoulder harness close to your center of gravity, which also increases BCD comfort.