Haute Complication: Patek Philippe Ref.5905 Annual Calendar Chronograph

Complications are great, but a combination of them is even better. The Ref.5905 Annual Calendar Chronograph delivers just that, in a way only Patek Philippe can do. With its first annual calendar introduced in 1996, the brand is actually the inventor of this complication. As it only needs manual adjusting every February of each year, it is less complex and expensive than a perpetual calendar, but far more convenient than a regular one. Ref.5905 also taps into the long-standing tradition at Patek Philippe to merge a calendar complication with a chronograph. No wonder that it quickly amassed its own share of admirers.

Next to its complications, plays also the design a significant role in the popularity of the model. With a diameter of 42mm, it has quite a wrist presence and allows for a prominent bezel while still offering enough room to space out all the features on the dial pleasantly. The calendar functions take up the top part of the dial, showing day, date, and month through separate windows. The bottom shows a subdial with the 60-minute counter of the chronograph, incorporating a day/night indicator.

To create the complex movement that powers the watch, Patek Philippe needed 402 parts. With a height of 7.68mm is caliber CH 28-520 QA 24H still relatively slender. In particular, when you realize that next to the annual calendar, it also houses the chronograph with flyback function and a full-size, centrally mounted oscillating weight in 21k yellow gold. As can be expected of a brand like Patek Philippe, they take the classic approach of constructing a chronograph, fitting it with both a column wheel and a vertical clutch. Precise timekeeping is further ensured by a Gyromax balance, equipped with a Spiromax balance spring. Patek Philippe offers this reference with a platinum case, which they combine with a blue dial with a sunburst finish. While this same finish also decorates the pink gold version, the brown color combined with this precious metal gives it an allure of its own, making the Ref.5905 a tempting proposition for a wide variety of Patek Philippe connoisseurs.