In 2004, Blancpain debuted a revolutionary equation of time watch, the Equation du Temps Marchante. Blancpain’s watchmakers undertook to bring to wristwatches, for the first time, the rare and difficult running equation complication that had existed only in large clocks and pocket watches. To do this they had to design an innovative gear train, with an ingenious differential that combines the running of the equation gear train controlled by a complex-shaped cam and the running train of the watch’s civil minutes-hand, to drive the running equation hand. In addition, caliber 3863 provides a plus/minus scale equation display. As befits this world’s first wristwatch, Blancpain combined these two separate equation displays with an innovative retrograde moon phase indication and a complete perpetual calendar. The decoration of the movement celebrates this achievement with a special hand carving of the bridges and a meticulously hand-fashioned winding rotor bearing an artist’s image of the sun.Reference 6638-3431-55B has a red gold case and a white dial in grand feu enamel.
