Quote Originally Posted by The Publisher View Post
At least with SAE threads a thread count per inch is specified! If metric threads have similar diameters but different thread pitches, they at least ought to call it out in the spec.
Although this no longer applies to the situation in the thread, just thought you might want to know. Metric has 2 different common threads and are labeled as pitch in mm. For example an 8mm diameter bolt can have a 1.25 thread or a 1.0 thread. They are usually labeled in the USA as "course" and "fine" as every size uses the actual size in mm of the thread. For example a 16mm diameter bolt can have a 2 thread or a 1.5 thread.

10,12,18, 20,& 22mm all have 3 different threads, just to add to the confusion.