Baker plunger type dial gauges (often referred to as dial indicators) are high-precision measuring instruments used to measure surface deviations, run-out, parallelism, and depth
A plain plug Gauge is a non-measuring limit inspection tool that is used to check the dimensional accuracy and tolerance of a bore or internal diameter. It has two cylindrical ends, the Go member that has to enter the hole, and the No-Go member that has to stay out of the hole.