Accuracy Guaranteed. The accuracy of this tire pressure gauge will astound you! It will read within .05 PSI, better than most tire gauges in the car care industry. The lithium battery is permanent, so it will never need to be recharged or replaced. That is great to know when you are in a bind, hoping you didn?t run your battery out before you needed a reading. This gauge is a work horse, reading air pressure from 5-150 PSI in « pound increments. When you are dealing with possible tire deflating, a quality and accurate reading is essential.