Schumacher SP-1 2/4-Amp 6/12-Volt Automatic Battery Charger/Extender Automatic charger for 6- and 12- volt batteries 6 Volts at 4 Amps, 12 Volts at 2 Amps Automatically determines if the battery is 6 or 12 volts Quick Connect Harness easily changes between battery clamp and ring terminals Ideal for power sport vehicles, motorcycles and small cars