Speeds you through the diagnosing of 12 to 24 volt automotive electrical systems. After connecting the clips to the vehicle’s battery, the automotive technician can determine, at a glance, the voltage level and the polarity of a circuit without running for a voltmeter or reconnecting hook-up clips from one battery pole to the other. The power switch allows the automotive technician to conduct a positive or negative battery current to the tip for activating and testing the function of electrical components without wasting time with jumper leads. Short circuit protected. Tests for bad ground contacts instantly without performing voltage drop tests. Allows you to follow and locate short circuits without wasting precious fuses. Tests for continuity with the assistance of its auxiliary ground lead. With a flip of the power switch, you will know at a glance that it is functioning without running to the battery. The 20 foot extendable cable allows you to test along the entire length of the vehicle without constantly searching for ground hook-ups. An absolute must for every automotive technician looking for a fast and accurate solution to electrical systems diagnostics.