High carbon steel body, high carbon steel manufacturing, the lens is made of PC glass mirror, grinding and polishing, anti-scratch and wear-resistant. Bidirectional shockproof, embedded precision gears, metal frame bidirectional shockproof. Metal limit, with locking screws, fixed calipers, more convenient to read. With micro-adjustable pulley, fast and easy to measure, reduce the measuring time, pulley micro-adjustment Measurement is more accurate. Where To Use: Perfect electronic vernier gauge for any small size measurement. It is the ideal measurement tool for a wide range of industrial, hobbyist and electrical applications.