Finally, a 9-volt rechargeable battery charger that is small, powerful and ready to go. Forget about the old method of waiting overnight for 9V batteries to charge, the new Powerex MH-C490F charger breaks the mold of an overnight charger by charging up to four 8.4 or 9.6-volt NiMH rechargeable batteries in just two hours. With the included car adapter, you don't have to worry about waiting until the battery is fully charged because you can pop the charger into the car and be on your way. The microprocessor automatically switches from rapid charge to trickle charge after the batteries are finished charging, so that the batteries will maintain their full capacity. Batteries not included. Charger measures 2.5" x 3".