I have already purchased this type of gauges. The problem in the past has been reliability. 1 out of 3 died after a few months, hardly used. It should replace one of them. They appear to be the same but it was about 2lbs less, the others appear to be totally accurate. I need to add 2 pounds to the reading. The last time I used it I didn't seem to get good readings on our bikes either for some reason, it only seemed to read a maximum of 30 when the tires felt very stiff. I'm not sure what's going on with this device.