Patek Philippe Complications 5905/1A-001 Flyback Chronograph - Annual Calendar

The Patek Philippe Reference 5905/1A-001 features a bold 42 mm stainless steel case with both polished and satin-brushed finishes, seamlessly integrated with a matching steel bracelet. Its sunburst olive-green dial radiates sporty elegance, punctuated by white gold applied faceted baton hour markers and faceted dauphine hands treated with white luminescent coating for enhanced legibility. Along an arc in the upper half of the dial, apertures display the day, date, and month, driven by the annual calendar mechanism, which only requires adjustment once a year. The central chronograph hand and the 60-minute counter reflect the flyback chronograph function powered by a calibre designed for performance with finesse.

Inside, the self-winding calibre CH 28-520 QA 24H blends the flyback chronograph with the annual calendar complication. It operates at 4 Hz via a vertical clutch, features a 60-minute counter, central chronograph seconds hand, and day/night indicator - all engineered for seamless precision. Built from 402 components and housing 37 jewels, the movement delivers a power reserve of 45 to 55 hours. It runs on a 21K gold central rotor, with Gyromax and Spiromax technology ensuring accuracy and long-term reliability under the Patek Philippe Seal. The transparent sapphire case back offers a view into this beautifully executed mechanism.