according to ISO 724
The dimension system for threads is based on the nominal dimensions for thread, pitch and minor diameter.
![basic concept and nominal dimensions](https://media.bossard.com/-/media/bossard-group/website/images/engineering/technical-resources-new/en/basic-concept-and-nominal-dimensions.png?la=zh-tw&hash=CB7198560F15A2E1F39E5684F5C8038E)
according to ISO 724
The dimension system for threads is based on the nominal dimensions for thread, pitch and minor diameter.