Calibre 2236 Is fitted by using a Syloxi hairspring that is produced by Rolex and patented. This silicon hairspring includes a patented geometry that assures the calibre’s regularity in any position. Lange & Söhne. I’ll clarify why: the German brand name stepped onto the chronograph phase with their Significantly-praised Datograph https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/