LISLE ULTIMATE CIRCUIT TESTER KIT -- Features heavy-duty coil cord extends over 8 ft. and a detachable, spring-loaded hook that pulls the center of the wire into the probe; Designed to find electrical shorts, checks polarity, detects battery drain, and checks circuits from a distance; Tests low voltage up to 28 volts; Needs alligator clip to attach to the probe during the clip-on connection.