Ms81-2021 Standard Pdf [extra Quality] -

Older drawings following "1st class" or "2nd class" tolerances are directed to Annex MS81-2021 Rev. 2 for continued compliance. Default Usage: In the absence of a specific class, (equivalent to higher precision) is generally required. 4. Permissible Deviations (Sample Data)

to define general tolerances for linear and angular dimensions of machine-cut parts. Key Details of the Standard Ms81-2021 Standard Pdf