Microprocessor controlled battery tester, with digital LED display. Allows testing without loading the battery. Easily select the correct battery capacity and rating system, to give an accurate view of the battery performance. Able to test batteries in or out of vehicle, and has a battery range of 100 - 1700 cold cranking amps. Includes reverse polarity protection, to protect the user, battery and device if the clamps are attached to the incorrect poles.