The RODAC Carbon Battery Tester is used to test the charge on 12-volt batteries, alternators, regulators and starters. It features a convenient carrying case, 35" 4G heavy-duty cable with 500 amp clamps, an analog dial for voltage and amperage, and a button for variable loads. It offers a 500 AMP charge capacity and checks batteries up to 1000 CCA / 160 amp hours, an automatic alarm after a 15 second test and a color-coded temperature compensation chart.