Made to fill up a large Therm-A-Rest NeoAir mattress in under a minute, the NeoAir Torrent Pump operates on four CR123A batteries, or plugs in to the DC adapter in your car, and lets you control exactly how firm you make your mattress. It also weighs only 9. 7oz, so you'll be able to throw it in the car or a pack without even knowing it's there.