I've just got permission from TrevM that it is public domain code (source: https://www.thingiverse.com/thing:311031/comments#comment-6423499) I've been finding myself ...

This is a remix of a remix from Thingiverse. It allows you to create metric bolts and nuts, along with other useful elements that I've modified. This library started from the work of Trevor Moseley ...

Tungaloy is expanding its TetraMini-Cut, an indexable thread turning tool series with four-edged insert, to include full profile threading inserts for machining external threads in ISO metric thread ...