This charger has it all with 6 and 12-volt capabilities, 2 or 4 Amp charge rates. This charger is ideal for charging/maintaining conventional acid batteries, factory-activated, maintenance-free batteries (AGM and gel batteries).  This fully automatic battery charger detects 6 or 12 volts, reverse polarity, overcharge, and short circuit protection in addition to testing if the battery is good, or needs replacing.  It has easy to read LED that indicates the power on, 6 or 12-volt selection, 1 Amp or 4 Amp charge rates, and the status of the battery charge. Comes with everything you need to include alligator clips or battery rings.