WORKS. I've used a 120w iSaddle car inverter to power a small compressor and a medium sized compressor and it works just as well as plugging the compressors directly into the car outlet. I tested it with an automatic vacuum cleaner and it worked. I tested it with the GPS system and it works again. I am very happy to have found a 12v inverter that works as advertised. I recommend the iSaddle 120W Car Inverter 110VAC to 12VDC Car Cigarette Lighter Adapter Converter because it works. Hope that helps.