The Higdon Pulsator Keeper is a steel cable keeper for the Pulsator. Use the Higdon Pulsator Keeper Cable as a safety precaution in case plugs on the pump, battery box, or extension cable come apart. Not using a keeper at a connection can result in loosing the battery box in the water. The keeper slips over the two plug ends and cinches down for a sure grip. The keeper works with all versions of the Pulsator.