Classique Chronometrie 7727BR "10hz" - Rose gold case on leather strap, rose gold folding clasp, hand-guilloché silvered dial, blued "Breguet" hands, small seconds, power reserve indicator, 1/10th second display, sapphire crystal and case back. The only piece from Breguet to feature a caliber with a 10 Hz frequency! The exceptional operating results of this watch are made possible thanks to a frequency of 10 Hz, improving the timekeeping performances of the balance-spring. Thanks to the mastery of silicon, this model features a double balance spring, lever and escape wheel made from this material, which has been specially developed for this piece, allowing it to reach a high frequency and optimal precision. This watch also features another major innovation: the use of a magnetic pivot. Thanks to this principle, Breguet was not content to simply limit the negative effects of magnetism on a mechanical watch, but managed to master them by improving the pivoting, rotation and stability of the axis of the balance. These innovations ensure that model 7727 has an average accuracy of -1/+3 seconds per day, a result better than the COSC norms, which are -4/+6 seconds per day.