dial bore gauge is a special purpose tool, calibrated in 0.001"
or 0.0001", which is used to quickly and accurately measure bore
dimensions, such as inside diameter, out-of-round, and taper. Dial
bore gauges afford a fast way of measuring, for example, cylinder
bore dimensions. A typical bore gauge consists of a shaft with a
dial indicator at the top and a measuring sled at the base. The
measuring sled is made up of three guides and an actuating plunger.