Hopkins Manufacturing Corporation makes your towing experience simpler and more rewarding through innovation and value. Hopkins offers a variety of towing solutions including vehicle wiring kits, adapters, vehicle and trailer connectors, breakaway systems and much more. Today, more than 40 percentage of retail category sales are generated from Hopkins innovations. This tool makes testing and repairing trailer wiring a easy one person job. Test lights and electric brakes with one tool. Includes battery terminal clips. Can be used with any 12 volt battery.