Calibre 2236 Is fitted by using a Syloxi hairspring that is made by Rolex and patented. This silicon hairspring features a patented geometry that makes sure the calibre’s regularity in any position. Lange & Söhne. I’ll clarify why: the German manufacturer stepped onto the chronograph stage with their much-praised Datograph https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/