Case material: Rose gold; Charge: Manual; Conditions: New Presentation condition : With boxes and all papers; Model: Datograph Price on request Gmtbroker Reference: 410.032 plates and bridges are made of untreated german silver decorated with perlage and glashutte ribbing. the plates, bridges, whiplash spring and classic column wheel are chamfered and polished. the balance cock is hand-engraved. the large two-digit date apperture is at 12. the day of the week subdial is at 8, with the small day/night indicator dial just above it. the moon-phase display is at 6 o'clock. the month subdial is at 4 o'clock, with the small leap-year dial just below it. this remarkable timepiece is the first to incorporate a perpetual calendar with a chronograph. the calendar is accurate until the year 2100, when, because the year 2100 is not a leap year (it is a century year that is not divizable by 400), the calendar will require a manual advance of 1 day. the moon-phase is itself an incredibly precise movement, accurate for 122 years, after which, it too will require a one day adjustment. an ingenious interlock device prevents accidental date resetting on the datograph perpetual. after pulling out the crown and disengaging the interlock, the perpetual calendar can be purposefully reset. the calendar mechanism alone accounts for 223 parts. a total of 556 individually assembled and adjusted parts constitute this superb watch. the watch is equipped with a stopwork (preventing overwinding and uncoiling) that ensures accurate torque delivery. the balance is by