Tests 6 and 12 Volt Batteries Up To 1000 Cold Cranking Amps: For conventional and maintenance _x005F_x005Ffree batteries in cars, light trucks, lawn tractors and RVs Simple To Use: Completely portable - external power source not required. Complete test done in 10 seconds Accurate & Dependable: Heavy duty, shock-resistant ventilated cover. Heavy duty, color-coded copper-plated clamps Tests: State of charge Cranking ability Charging system output Starter motor draw