3-position charger rate selector switch: Trickle charge for motorcycles, snowmobiles, all-terrain vehicles, lawn and garden tractors and most other small engine charging applications; 10-Amp continuous charge for automobiles, trucks, tractors, and vans;50-Amp power booster for emergency and quick engine starts. Charges maintenance-free, deep cycle, low maintenance and conventional type 12-Volt batteries. Solid state silicon diodes for peak performance output. Deep louvered all-steel case with baked enamel finish, insures excellent ventilation for long life component performance. Heavy-duty copper wound, steel laminated transformer is energy efficient to insure max performance and component life. Flush ammeter.