Ring gauge

A ring gage is a precision measurement tool used often by industrial manufacturers. Made of a thermally stable material, such as steel, a ring gage is cylindrical in shape with almost perfect geometric symmetry and a very precisely determined internal diameter size. Ring gages can be used either as a point of reference to set other measuring tools or as a means of checking the size and/or roundness of a part. These processes are known as indirect and direct gaging respectively. Ring gages also come in three main varieties: go ring gages, no-go (or not-go) ring gages, and master setting rings.