Ojiyas standard thread gauges consist of thread ring gauge and thread plug gauge that fits perfectly. The elements of the screwed parts are made extremely similar to the basic profile of the screw thread. These gauges are not specified in JIS and differs from limit thread gauges, which are usually used in mass-production line. These gauges are suitable for inspecting small amounts of screws which must be engaged perfectly. The screws to be checked should be fitted perfectly as far as possible to the thread gauges.