The Schumacher 6/12V Wheeled Fully Automatic Battery Charger and 40/200A Engine Starter is built for heavy-duty charging needs, perfect for engine starting and charging SUVs, trucks and other large engines. This unit is also a battery and alternator tester, providing charge level and helping to diagnose electrical problems. From Schumachers Wheel Charger line, this unit offers 200A Engine Start, 40A Boost and 6/2A Charge/Maintain rates.