The perpetual calendar provides day, date, month and moonphase while the chronograph lets you time events.
The 18k yellow gold case is in mint plus condition with dimensions of 36.5mm diameter by 13.5mm thick. Domed sapphire front crystal and flat sapphire display back crystal. Pump style chronograph pushers.
The following information is presented on the dial: 3 o’clock subdial shows leap year cycle and 30 minute chronograph totalizer; 6 o’clock subdial shows moonphase and date; 9 o’clock subdial shows constant seconds and 24 hour time. Day and month are displayed in the apertures above the “PATEK PHILIPPE GENEVE” text.
Movement is the manual winding Caliber 27-70Q with 24 jewels, adjusted for hot and cold, and bearing the Geneva Seal. The chronograph features column wheel construction.
Includes letter from Patek Philippe confirming the 18 C. yellow gold bracelet is factory. A copy of the letter is on the following page.