A coupler for a cable includes a body portion having integral first and second ends and an integral gate having a key entry region, wherein the body portion has a free space at least partially enclosed by an inner surface of the body portion and the gate. A complimentary coupling ring includes an integral perimetal body having a head section, a foot section, and two arm sections therebetween, wherein at least one of the arm sections has a key region, wherein the key region consists of a solid, integral portion of the at least one arm section. A coupler/coupling ring assembly comprises a coupler and a coupling ring that is removeably engageable with the coupler. The coupler/coupling ring assembly is suited for interconnecting lengths of cable, particularly suited for, but not limited to, undersea applications such as attaching a seismic data recording device to the coupler via the coupling ring.