110V AC worldwide Voltage ,60/50Hz, 12-13.8V DC, 5V DC 2-individual charging channels enables you to charge 2 or 4 pieces of same or different types(Nimh/Nicd), battery must be the same size and type. Negative Delta V Cut off feature to 100% protect your batteries With over-temperature and reverse polarity protection Could be charged by AC Adapter or external car adaptor It is recommended to charge batteries of same capacity in each charging process.