MobilePower InstantBoost 400 6 - in - 1 Power Inverter. It's portable power you can depend on. Get yours for . ... The key turns, but the engine won't. Good thing you brought the 400w Power Pack along. Convenient unit charges up with either standard wall current, or 12v mobile current, and stores neatly in your trunk. When needed, it eliminates the need for another car and a pair of jumper cables. Connected to your power cell, the Boost 140 sparks a big jolt over two heavy - duty alligator-clip cables. Plus, there's also a built - in air compressor to keep your tires, inflatable rafts, and other air - pumped gear ready to go, and on-board 120v, 12v and USB power ports to keep all of your gear, gadgets, and appliances juiced up on the go. Portable powerhouse: Vehicle jump - start with 500 cold - cranking amps and polarity protection Built - in rechargeable lead - acid battery Dual 12v covered DC ports USB outlet port 260 - psi air compressor with gauge One 120v covered outlet U