The Model i4 Charger is a universal, automatic smart-charger compatible with almost all types of rechargeable batteries. It will automatically identify battery type and apply the appropriate charging mode. Each slot is microcomputer-controlled capable of charging different battery types simultaneously and stopping when complete. Reverse polarity protection is provided. Works on any voltage between 100 and 240V, and a 12V car power cord is included. A superb piece of gear.