USB and 12 volt ports to vitality your cell phones, pda or any tool chargeable through such a port.Plug into any accessory outlet in your car, wait 15-20 minutes and begin your car.No further asking strangers for a bounce, re-charge your battery for an emergency start from the protectedty of your car. Never be stranded once more. This good little unit allows for protected charging of your battery without leaving the securety of your vehicle. Don’t ask strangers for a soar again..Source from Schumacher EC-4000-USB Large Emergency Glove Box Charger w/USB port