Crappy alloy wheels on my car with fancy low profile tires have endless slow leaks every winter. Got it to keep 'em up Arrived fully charged and ready to use which was a nice touch. I'd say it took about 1 minute to put just over 4lbs in a 35psi tire (lowest) and then put 1-3lbs in the other 3 tires. It was definitely close to cooling off, but it did exactly what I needed. It lags a little behind the setting, the auto shut off worked at 34.7lbs but I can easily compensate for that next time by just setting it to 36 and even manually stopping it at 35. It does not come with an AC adapter or car charger and can only be charged with a USB cable. There is room for an AC/car connection but you will need to find your own compatible adapter for this. It's a bit noisy but sounds like any other small air compressor. I will keep one of these in my travel tool bag forever. After using it for a while, I'll update this review with some notes on durability, charge retention, etc. The instructions are almost useless and contain very little actual operating information. You'll have to do a bit of guessing to figure out what the on-screen information is for and what it means. I was able to figure it out enough to make it work, but I can't say part of my success wasn't luck.