Ring gauges, often named ring masters, are used in applications where the effective part diameter must be inspected or where ring gauges are preferred because of consistent calibration they provide. Ring gauges are outside diameter type fixed gages. Ring gauges are widely used for limit measurements on cylindrical components. To obtain "Go / No-go" principle a pair of ring gauges is used. To distinguish them, "No-go" ring has annular groove cut through the knurled gripping surface. Ring gauges are made to precise tested sizes and have gaging surfaces of hardened steel, chrome plate or tungsten carbide to prevent wear.