A long time ago I got a relatively inexpensive dial indicator that was accurate to 1 pound. A few years ago I switched to a not too expensive Milton inflator. Both were difficult to read. A year ago, TPS pressure gauges started showing lower pressure than pressure gauges. I didn't know which number to believe. I used this inflator tonight - what a treat! Turns out I've lost 4 pounds less weight in both cars over the last year. I suspect I dropped the dial indicator and ripped it out of calibration - now I understand the value of that fall. Reading about sensors, I learned that digital sensors are inherently more accurate and will likely remain so. I have replaced alkaline batteries with lithium batteries because many expensive electronic devices have been destroyed by leaking alkaline batteries. Expensive but worth every penny and I hope to have it for many many years to come.