This looks pretty good at first glance, but I think it has a pretty serious problem: the tension required to move the gauge in the case is almost ZERO , and not being able to read the sensor when pressed against the tire almost always results in an incorrect reading, since the moment you pull it back the sensor is almost ALWAYS off from the correct reading. I found a way to fix it myself, but you have to gut it to fix it and that will almost certainly screw it up. A simple fix during the manufacture of the tread depth gauge makes it a 5 star tool, but one I can't get better than 3 stars. Color coding is good, but some colors' numbers are hard to read unless you're in bright light.