The best line from this factory tour at SME [0], a maker of high precision audio [1] is, 'we make our own screws'. [2]
[0] History of SME, http://www.sme.ltd.uk/content/History-1307.shtml [1] http://www.sme.ltd.uk/content/History-1307.shtml [2] https://www.youtube.com/watch?v=q2xQkexHT-M