If you travel often and take your car or truck all over, you might wish you could use it to power up your laptop, video game system or other devices. Power inverters make this possible. One inverter unit will convert your vehicle's battery--DC power--into usable AC power with one or more outlets. Inverters are also quiet and don't use fuel. However, to be sure the unit works for you and your vehicle, use these inverter selection and usage tips.