In the Big Pilot's Watch Annual Calendar Spitfire, the calendar shows the month, the day of a month and the day of the week in three separate windows. The order corresponds to the American spelling. The switching mechanism automatically takes into account the different lengths of the individual months, once a year - at the end of the month of February - it must be manually corrected by the crown. The dial-colored dial bears on the right and left two Compteure with the power reserve indicator and the small, red marked second. The 52850 manufacture caliber, thanks to the power of two barrels, provides the higher torque needed to drive the three display slices of the annual calendar.