An indicator is any of various instruments used to accurately measure small distances and angles, and amplify them to make them more obvious.
Calibration of accuracy and repeatability on Dial Gauge / Dial Test Indicator, which using JIS B 7503: 2011 – Dial Gauge and JIS B 7533: 1990 – Dial Test Indicator (Lever type).
Figure 1: Dial Guage
Figure 2: Dial Test Indicator