HTC HD7 Car Charger [OEM] SPN5400 Charge your cell phone when you're on the road. Use the time you spend in your car to make sure that your phone is ready to go. Car charger plugs into your car's cigarette lighter and charges your phone while you're driving. Intelligent IC chip recognizes a fully charged battery and automatically switches to saver mode to prevent overcharging and short circuit. Plug never heats or overcharges the battery.