Rally Marine Grade 20 Amp Quick Battery Charger and Maintainer with Microprocessor (7633) Use on all 12 volt lead acid, marine, AGM and gel batteries Corrosion resistant circuit board and clamps with spark resistant reverse hook-up and overcharge protection Selectable 2,10, or 20 amperes charge for all your needs, from trickle to quick charge High frequency technology delivers a faster amd more efficient charge; built in microprocessor technology monitors the battery charge to provide the best condition to prolong battery life 3 Minutes to Start, Approx. 2.5 Hours to full charge