I have a small commercial 6 gallon compressor in my garage. I use it mainly for blowing out PC cases etc. I've had a tire inflator for a long time that has the stem sticking out to show pressure. Worked well but wouldn't close, had to press the valve hard to close. I wasn't sure how this locking swivel would work. The trick is to open the clamp and squeeze firmly to create a good seal, then release to lock. Then it just freezes. The pressure gauge works as soon as you block the pressure valve, it shows the current tire pressure. Then squeeze the lever and inflate the tire and watch the arrow move to the desired pressure. Too much air? Oh. Just press the small release valve button to release a little. It's a lot easier than my little portable car compressor which has to be screwed in and it's slow to fill. I only have a 3-4 gallon compressor that I fill up to 110psi. It was easy to mount all 4 tires. So far this is the winner.