Calibre 2236 Is fitted with a Syloxi hairspring that is made by Rolex and patented. This silicon hairspring provides a patented geometry that guarantees the calibre’s regularity in any position. Coupled with his colleague Thomas Earnshaw, the pair would build simplified and practical marine chronometers. #Watches The Working day-Date has https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/