Features and Benefits: Quickly tests light circuits;cleans and repairs truck and trailer connectors Great preventative maintenance tools that also extend harness life Connector cleaner can be used as a pin-wear gauges The 7-way Round Pin Towing Maintenance Kit provides the tools necessary to maintain trailer electrical connections. The innovative set includes a 7 Round Pin Tester 2 Pin Cleaners and DeoxIT® terminal enhancer for testing cleaning and rejuvenating both male and female connections. Reduce guess work enhance harness life and keep your fleet on the road with the 7-way round pin Towing Maintenance Kit.