is easy to read, easy to use and importantly (to me) it is displayed in millimeters. No more guessing with an eye gauge, you can measure tire tread depth quickly and easily with the Slime 20177 Tread Depth Gauge. I use this information to measure the performance of my suspension. Is the tire wear even, is the pressure correct? It seems quite durable, especially for the price. Keep it in your glove box or tool box! In short, recommended. Using this Slime 20177 Tread Depth Gauge along with a TEKTON 5941 digital tire gauge, 100psi, I was fine tuned to monitor the condition of the tires and avoid sudden changes.