ISO/CD 21937
ISO general purpose metric screw threads --- Limits of sizes
Reference number
ISO/CD 21937
Edition 1
Committee Draft
ISO/CD 21937
A draft is being reviewed by the committee.


This document specifies the limits of sizes for the major, pitch and minor diameters of ISO general purpose metric screw threads (M) conforming to ISO 261 having basic and design profiles in accordance with ISO 68-1. This document is applicable to the metric fastening screw threads with the ten recommended tolerance classes specified by ISO 965-1.

General information

  •  : Under development
    : CD approved for registration as DIS [30.99]
  •  : 1
  • ISO/TC 1
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