This cable is for the CCD reversing camera systems that have waterproof connectors. It is 2m long and comes with a rubber O-ring on the screw fit connector. This makes the join waterproof. It is useful if you did not buy a long enough cable with your reversing system! It is important to check the design of the plug matches yours as there are a number of variations of 4 pin connector available. The type of connector is often referred to as an aviation connector.