The sliding vernier scale is easy to read and has no cams, gears, or levers to wear out. Pocket Durometers are unbreakable, lightweight, and easy to carry around the plant for on-site testing. The scale is divided into 5 point increments from 0 to 100. Scale holds maximum reading making it ideal for testing hard-to-reach areas. Measure 1/2"W x 4-1/2"H.