A bore gauge is a precision measuring tool used to determine the internal diameter of a cylindrical object, such as a pipe or hole. It typically consists of a measuring head with adjustable arms that expand to fit the bore, allowing for accurate readings. Bore gauges are essential in various industries, including manufacturing and engineering, to ensure that parts meet specific tolerances. These tools come in different types, including dial bore gauges and digital bore gauges, each offering unique features for measurement. Proper use of a bore gauge helps maintain quality control and ensures that components fit together correctly in assemblies.