Incorporating a self-winding flyback chronograph and a patented annual calendar, Patek Philippe Reference 5905 belongs to the brand’s Complications family.
Launched as a platinum model in 2015, then in rose gold in 2019, Reference 5905 is now available for first time in stainless steel. Fitted with a three-link integrated bracelet, it boasts an elegant and contemporary-styled sunburst olive green dial.
The dial ensures excellent legibility for the additional functions, with a central chronograph hand, a large 60-minute subdial at 6 o’clock and three day/date/month apertures arranged in an arc for instant reading of the Annual Calendar indications. There is also a discreet day/night indicator at 6 o’clock that is useful for ensuring accurate date setting.
The caliber CH 28-520 QA 24H remains faithful to the traditional column wheel for the transmission of chronograph commands. However, instead of a toothed-wheel horizontal clutch, it has a vertical disk-type clutch.
This modern technical solution causes almost no wear and tear, and the central chronograph seconds hand can also be used as a permanent (running) seconds display. The patented Annual Calendar automatically takes account of 30- and 31-day months, requiring only one correction per year, on March 1st. This movement is visible through the transparent sapphire caseback.
The polished steel case features a sophisticated construction with a concave bezel and recessed sides. The integrated steel bracelet is inspired by that of the Aquanaut Reference 5167/1A with its contrasting finishes (polished outer links and satin-finish inner links), while subtly distinguished from it by the underside of the bracelet and the edges which are polished, in line with the case. It is equipped with a patented Patek Philippe fold-over clasp secured by four independent catches.
Model: Patek Philippe Self-winding Flyback Chronograph with Annual Calendar, Reference 5905/1A-001 (in steel with an integrated bracelet and a sunburst green dial)
Caliber CH 28‑520 QA 24H
Self-winding mechanical movement
Diameter: 33 mm
Height: 7.68 mm
Power reserve: min. 45 hours – max. 55 hours
Winding rotor: 21K gold central rotor
Frequency: 28,800 semi-oscillations/hour (4 Hz)
Balance spring: Spiromax®
Hallmark: Patek Philippe Seal
Central chronograph hand and 60-minute counter
Day, date, month and day/night indication displayed in apertures
Olive green sunburst, gold applied hour markers
Sapphire crystal case back
Water-resistant to 30m
Diameter: 42 mm
Height: 14.13 mm
Integrated Steel bracelet with fold-over clasp