This inflator is the best that I've ever used. It took me a few minutes to figure out why it wouldn't turn on when I connected the battery. It was a small piece of plastic insulation that prevented the electrical contacts from joining. Once I removed that, it worked perfectly. I really like being able to set the inflation pressure and letting the inflator do the rest. I learned to leave it connected until the sounds stop completely. It over-inflates slightly and then lets air out until it reaches the pressure that you set. I both the quick valve connectors to use with it and they work well and are quicker than screwing the nozzle on and off. The inflator is small compared to others that I've used. I inflated 7 tires with pressures from 20 psi to 60 psi and the battery didn't need to be recharged.