The Snap-on 12V Digital Display Circuit Tester with USB Plug, No. EECT402USB, plugs into USB ports and comes with a 12V CLA adaptor for older models, eliminating the need to maneuver outside the passenger compartment to connect to the vehicle's battery. The patented Instinct clear handle lights red for power or green for ground, and offers one-hand operation leaving the other free to jiggle wires, replace fuses, or operate switches. It has a stainless-steel corrosion-free shank, backlit LCD digital display and comes with an 18-gauge coil cord that stretches 13".