If the query is a typo for MS F1 2021e, it refers to a standard for general tolerances in machining.
Once you have the official PDF:
Only if the standard has been “canceled” and not replaced, or declared “unclassified and unlimited distribution.” Check the DLA ASSIST Online database. Most active MS standards are now copyrighted by SAE and require purchase. ms812021 standard pdf best
Numerical Limits: For nominal dimensions up to 6 mm, the "1st class" tolerance is typically set at ±0.1plus or minus 0.1 Understanding MS 81 vs. Other Standards If the query is a typo for MS
EverySpec is a private, curated repository of thousands of military standards. Why it's best: They clean up official PDFs,
Here is what you need to know to secure the best version of this critical specification.
everyspec.com.