When you wanted buy some M thread ring gage ,please tell us what standard you need?

ISO standard or Asme B1.13 standard, they are not the same gegs.

The ISO 1502 gaging system is different from our own B1.2 standard. Setting masters are not made to product limits. GO gages are made with wear allowances. Attached is a layout of the 2 systems with the limits for this thread.

     Sowant precision gage can offer you correct gages which you need, of course we can offer your gages per your drawing,   we can offer ACME thread gages, STUB Acme thread ring gages, API 5b thread gages, REG working ring gages, REG working plug gages, NC working ring gages, NC Working plug gages, FH thread gages, IF  thread gages. Any question,let me know.