Experienced mechanics know that a powerful wheel charger is an essential ingredient for any well-equipped professional garage. And while some mechanics prefer fully automatic chargers, others want a charger that gives them complete control over each process. For these mechanics, the answer is a Schumacher DSR ProSeries manual wheel charger. The Schumacher DSR ProSeries Automotive 6-Volt/12-Volt 225-Amp Manual Wheel Battery Charger and Jump Starter (DSR139) features a 135-minute timer that gives you control over every facet of charging with multiple charging options. The unit features a 225 cranking amp (12-volt) engine start, which is enough power for cars, SUVs, trucks, boats, and other large engines. The DSR139 also includes three boost modes-50-amp (12-volt), 25-amp (12-volt), and 25-amp (6-volt)-for quickly adding charge to a deeply discharged battery. It also includes a 10-amp 12-volt charge mode for basic battery charging.