Review on Kensun 12V DC Portable Air Compressor Pump - Enhanced 150W Digital Tire Inflator for Cars & Inflatables: Efficient and Reliable Performance by Jason Yancy

Used this product for the first time. As some others have mentioned, the air pressure gauge will drift quite a bit. I had to set the gauge to 44psi to get 39psi in my tire according to my reliable gauge which I know to be correct. You also need to turn on the pump before screwing the air hose to the tire because the pump will stop immediately if you turn it on after the air hose is attached to the tire. It's just okay, but not as good as I was hoping. Update 12/29/2015: Kensun customer service was very helpful and sent me a new air pump free of charge as I was not satisfied with the first one. However, the new one they sent me doesn't work at all. The pressure gauge shows the tire pressure, but the air pump does not start when the switch is turned on. Engine noise is heard and nothing. I've tried both with the air tube connected to the tire and not connected to the tire and the results were the same in both situations. I replaced the fuse with a spare in case it somehow caused the engine not to start, but that didn't make a difference either. Without the good customer service I would have downgraded my rating to 1 star. Update 4/28/16: Kensun customer service is very helpful and sent me a second replacement and an AC/DC adapter so I can connect the compressor to my 120 volt home outlet. The 2nd refill gauge now only reads 2psi instead of 5psi like the original I got. I can live with a difference of 2 PSI. The main problem I still have is that even with this second replacement unit the compressor will not start if the inlet hose is attached to the tire as specified. If I start the supercharger motor and then attach it to the tire it works. But if I then stop the compressor and try to restart it it won't start again as long as it's still attached to the tire, I have to unscrew the inflation hose from the tire, start the compressor motor and then screw the hose back onto the tire. tires again. Overall, I've raised my rating from 2 to 3 stars based on Kensun's excellent customer service and the fact that the gauge on the second replacement part is only 2psi off. If the supercharger motor started as intended when attached to the tire I would be perfectly happy.