Screwing

https://en.wikipedia.org/wiki/Screw

https://en.wikipedia.org/wiki/List_of_screw_drives

https://ecal.ch/en/4081/elac-gallery/exhibitions/-u-joints-exhibition

https://www.schrauben-preisinger.de/

https://www.hoerr-edelstahl.de/Befestigungsmaterial/Schrauben/

 

DIN

Whitworth