Measurement tools have various types; major products include vernier calipers, micrometers, dial gauges, gauges of varied types, bubble levels, protractors and rulers; they are tools used in production processes and quality checks. Some of these products have inspection certificates or calibration certificates attached to them, or conform to JIS standard, ISO standard, etc. Measuring instruments, on the other hand, include equipment to measure various states such as current/voltage, weight, temperature, hardness, water quality, viscosity, flow rate and surface roughness. Some of them not only digitally display the measurement results, but also transmit data to record/display on external devices.