The design of thispaid tribute to the precision clocks that were long used to display the exact time in watchmaking workshops and astronomical observatories. It was launched as Ref. 5235, in a white-gold case framing a two-tone silvery gray dial with a vertical satin finish. Now the manufacture has given a new face to its Annual Calendar Regulator by presenting it in rose gold, its two-tone dial in graphite and ebony-black with a vertical satin finish and white transfer-printed indications. This highly original design, enriched by the rose-gold baton-style hands, is again reminiscent of the old regulators. It accentuates its elegant technical air with three railway-track scales, one each for the main dial and the subsidiary hour and seconds dials. The Annual Calendar displays the day, the month and the date in three generous apertures, automatically taking account of months of 30 and 31 days. It therefore requires correction only once a year, on March 1st.
The caliber 31-260 REG QA self-winding movement, developed for this model, is notable for its frequency of 23,040 semi-oscillations per hour (3.2 Hz) and its high-tech regulator incorporating a Pulsomax ® escapement and a Spiromax® balance spring in Silinvar® – both developed by the “Patek Philippe Advanced Research” department. The minirotor in 22K gold adorned with circular Geneva striping, together with all the other finely decorated parts, may be admired through the sapphire-crystal case back.