Intercomp Tire Hardness Durometer, 0-100 The surface of a tire becomes harder with every heat cycle and even new tires of the same compound can vary a great deal in hardness. If a tire is too soft for the track, it will overheat and may not last the entire race, but if it is too hard, it will not get up to the optimum temperature and traction will be sacrificed. Intercomp's Tire Durometer enables you to make the correct tire selections for any track. Type-A Removable Tip Reads from 0-100 Adjustable face Zero Dial ASTM Certified Includes: * Case