Bore Gauge

A bore gauge, also known as a dial bore gauge, is a precision measuring instrument used to measure the inside diameter of cylindrical holes, bores, and cylinders. It is designed to accurately determine the internal dimensions of objects such as engine cylinders, pipes, bearings, and other machined or manufactured components with cylindrical openings.

Using a bore gauge involves inserting the measuring head into the bore to be measured and then carefully expanding the arms until they make contact with the bore’s inner walls. The measurement is read from the gauge’s dial or display, indicating the diameter of the bore at that particular location. Bore gauges can come in various sizes and designs to accommodate different bore diameters and depths.

Mitutoyo 511-753 Bore Gauge – Amazon.com