The PV400USB 400W PowerVerter® Ultra-Compact Car Inverter provides 400 watts of portable power for charging and operating multiple devices in your car, truck, boat or RV. It converts 12V DC power into standard 120V AC power to run a wide variety of electronics, such as laptops, smartphones, tablets, game systems, portable TVs and DVD players, MP3 players and GPS units, as well as low-power lights, camping accessories, battery rechargers for small battery-operated power tools and mobile office equipment. The PV400USB features two AC outlets, a 2.1A USB port and a 1.0A USB port. Just plug the DC input jack with convenient 3-foot cord into the 12V cigarette lighter socket in your vehicle, or use the battery cables to connect to your battery - always connect red to red and black to black. Press the on/off button, and the unit is ready to operate. Easy-to-read LED lets you know the inverter is receiving power from the battery.To prevent you from running down your car battery, the PV400USB turns off automatically when the input voltage falls to 10V. Likewise, the unit will also shut down if it gets too hot (for instance, because your connected devices exceed 400 watts). A built-in ventilation fan keeps the interior cool during extended use. The durable plastic housing is engineered to withstand the rigors of road trips, campouts, business trips and family vacations. No maintenance is required.