This standard is a limit gauge used for dimensional inspection of metric threads specified in JIS B 0209 and JIS B 0211 [hereinafter referred to as limit gauge for threads]. ) and the gauges used for inspection and adjustment (hereinafter referred to as inspection gauges and adjustment gauges). Note that the thread limit gauge, inspection gauge, and adjustment gauge are collectively referred to simply as gauges. Gauges according to this standard shall be used for testing, although other testing methods may be used, such as measuring with an indicating instrument. The purpose of this standard is to specify a means of distinguishing workpiece threads that meet within tolerance limits from others. In order to ensure compatibility of workpiece screws and avoid disputes between producers and users, the following principles shall be applied: a) The producer shall not ship any workpiece screws whose actual thread dimensions (e.g. single effective diameter and combined effective diameter) are outside the specified limits. b) The user shall not reject any workpiece thread whose actual thread dimensions (e.g. single effective diameter and combined effective diameter) are within the specified limits. In order to meet these two principles, this standard specifies the types and dimensions of gauges necessary for the inspection of screws, the conditions for using these gauges and the inspection of machined screws.