M-type thread refers to the common thread, that is, the national standard thread, ‌, where "M" represents the type of the thread, ‌ and the number behind M indicates the metric diameter of the thread. ‌

M-type metric thread can be divided into two kinds according to the pitch: coarse ordinary thread and fine ordinary thread,

Coarse ordinary threads generally do not indicate tooth spacing, as the default value, need to check the thread pitch table,

Fine ordinary threads must be marked with tooth spacing.

Take the M10 thread as an example:

The standard pitch of the M10 is 1.5mm. ‌

The M10 thread is a thread with a diameter of 10mm, ‌ it is a coarse thread. ‌ Internationally, the standard pitch of ‌M10 thread is defined by the International Organization for Standardization (ISO) as 1.5mm. ‌ This standard pitch ensures the interchangeability and versatility of the thread, ‌, so it is widely used in machinery and equipment, ‌ automobile manufacturing, ‌ construction engineering and other fields. ‌ In addition, the ‌M10 thread pitch standard is also divided into coarse pitch and fine pitch, ‌ where the coarse pitch standard is 1.5 mm, ‌ and fine pitch has different standards, ‌ including 1.25 mm, ‌1 mm, ‌0.75 mm and 0.5 mm. ‌ These fine pitch standards are suitable for different applications and requirements ‌ provides more choice and flexibility 12. ‌

In addition to the pitch, the thread grade of the tolerance zone is sometimes marked, such as M10-h7, M10-h6, etc