The Lisle Parasitic Drain Tester - 64970 is a diagnostic tool used to test the parasitic drain current of a vehicle's electrical system. It is designed to quickly and accurately measure the amount of current draw from a vehicle's battery when the ignition is off. It features a digital display that shows the amount of current draw in Amps, a low battery indicator, and an easy to read LED display. It is powered by a 9V battery and includes a test lead set.