This round tire gauge is both easy to use and simple to read. Attach to the tire valve connector and this gauge will measure your tire's air pressure from 10 to 110 PSI. Tire PSI reads easily with large numbers on the gauge dial. Measurements lock-in when completed and reset at the press of the side button. Valve connector also includes a deflater that makes it easy for you to release excess air to achieve precise tire pressure (Tire Gauge accuracy +/- 2 PSI).