This gauge is used to check the wear of the GO thread limit gauge (GP, GR). Conventionally, for JIS Class 2 grades, the GP and GR do not pass through, and for 150 grade 6H, the GP and GR do not exceed 1 revolution, so it is judged that they are within the wear limit.
* The wear check ring gauge (GPW) is not specified in JIS and is set by OSG. Please give due consideration before use.
