Heritage Logical One High-precision, fine Swiss watchmaking Romain Gauthier’s award-winning Logical One features a revolutionary, friction-minimising ruby-link chain, snail cam and sapphire-lined mainspring barrel to offer nearly two days of constant force – the holy grail of precision watchmaking. Logical One calibre Pioneering 'chain-and-fusee' constant-force mechanism Learn more Find us Visit one of our retailers to see this watch in the metal Find a retailer