Calibre 2236 Is equipped which has 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 posture. Furthermore, all 3 watches take advantage of a concealed attachment technique that guarantees seamless visual continuity involving the bracelet https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/