6V/12V, Battery Charger, 100A Engine Start, 30A Boost, 6<>2A Charge. Advance 5-Stage Charging, 100A Start it now – Instanty start a vehicle with a dead battery. 30A Boost – Quickly bring a deeply discharged battery to 75% full charge. 6A Charge – ASafely and precisely charge & maintain all lead-acid & AGM batteries. Battery Health indicator – For battery status, good health, service battery. 6V/12V Auto-Voltage Detection – automatically detects 6V or 12V batteries. Digital Display – real-time feedback of the charging status. Stop/Start Button – Manually starts charger for use on batteries with low as zero volts. Alternator Testor – Checks voltage outout of vehicle alternator. Solid performance, & long-lasting durability make this charger a great choice for professionals. Its energy efficient & fully automatic.