My Mom gave me one of these for Christmas, I honestly didn't expect much but litterally as a truck driver, it easily airs up my semi tires to 100 psi and 110 Psi on the steer tires at least twice on a standard 20 watt DeWalt battery. I have noticed that generic batteries do work fine, but sometimes need to be slapped on a bit hard. My wife can check tire pressure with a standard tire gauge, but has a hard time actually airing up a tire if it's low, but she can easily just clip on this device and press the trigger a time or two and it stops at 37 psi where I set it. I honestly think this is probably the best tool I've ever bought for the dollar value and my wife doesn't have to find someone to help her put air in the tires if I'm not there, it's essentially just like checking tire pressure and inflating to desired pressure with a few clicks and a few trigger pulls.