Calibre 2236 Is equipped by using a Syloxi hairspring that is made by Rolex and patented. This silicon hairspring includes a patented geometry that makes sure the calibre’s regularity in almost any posture. The third major phase happened in the early 1900’s. The shape in the timekeeping equipment changed in https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/