The Schumacher SCDSR122 DSR ProSeries 275 Amp(12V) 125 Amp(6V) 15 Amp 4 Amp 6V/12V Fully Automatic Pro Smart Battery Charger with Engine Starter, Boost, and Maintainer is a powerful battery charger that can charge a variety of battery types. It features a built-in engine starter, boost, and maintainer to keep your vehicle running smoothly. The charger is also equipped with a 4 amp 6V/12V output for charging larger batteries. The Schumacher SCDSR122 DSR ProSeries 275 Amp(12V) 125 Amp(6V) 15 Amp 4 Amp 6V/12V Fully Automatic Pro Smart Battery Charger with Engine Starter, Boost, and Maintainer is a powerful battery charger that can charge a variety of battery types. It features a built-in engine starter, boost, and maintainer to keep your vehicle running smoothly. The charger is also equipped with a 4 amp 6V/12V output for charging larger batteries.