In case I come across here as too harsh in these guys, it’s not like this air compressor machine is rocket science. The instructions are clearly and simply stated on the cover. All you have to do is stick the nozzle on the tire stem and it automatically begins pumping air. The air pressure number is digitally shown on the front of the machine, but you don’t have to see it. Once you reach the max needed in your tire a beeping alarm goes off so you know to stop. That’s it. Simple – simple.