Schumacher SE-1275A 2/12/75 Amp Automatic Onboard Battery Charger A 6 function rotary switch prevents overcharging. Made for 12V batteries. 75-amps help emergency engine starting. 12-amp fast charge charges batteries in 2-5 hrs; 2-amp trickle charger charges batteries in 2-12 hrs. 2 LED lights display charge status.