Kris Bubendirfer: " A revolutionary 100% in house design and manufacture. Meyer and Stuedeli SA (MST) third in-house automatic. This calibre along with the 471 successor was the pinnacle of MST movement design. Differential gearing, 44 functional jewels and beautifully finished - this world class movement was many years ahead of the competition. Micro regulator as standard. Jewels in the 44 jewel version were allocated as follows: Movement 19, automatic winding device 8 (hole jewels), coupling clutches (2x5) 10 ruby balls, and ball bearing for rotor 7 ruby balls."