Patek Philippe Annual Calendar Flyback Chronograph

Overall Condition: Excellent condition overall. Case shows light signs of wear. Dial and matching handset are excellent.

The annual calendar is a complication invented by Patek Philippe.

While it plays second fiddle to the perpetual calendar in the minds of most collectors, the reality is that the construction of this calendar mechanism is by no means a simple feat, and requires impressive micro-engineering and design acumen to execute well. Able to account for months of different lengths, it only requires manual adjustment once per year — at the end of February.

This particular piece is no ordinary annual calendar: A Reference 5905/1A-001 from the 2020s, it also includes a flyback chronograph — one in which a single button press both stops and instantaneously restarts the chronograph. Convenient for timing laps, this complication proves unbeatable when combined with the utility of an annual calendar.

This particular 5905/1A is housed in a 42mm stainless steel case with a signed crown, square pushers, a polished, concave bezel, and a sapphire crystal. It features a luminous striking green dial with applied indices, a white minute track with a radial subsidiary register, a matching luminous ‘obelisk’ handset, date, month, and day apertures, and a running seconds sub-register above 6 o’clock. To help accentuate the striking dial, this watch is paired with a full stainless steel bracelet.

Flip the watch over, and one is greeted — via a sapphire exhibition caseback — with a view of the automatic Patek Philippe Calibre CH 28-520 QA 24H movement. This is simply a stunning timepiece in every regard: horologically, aesthetically, and functionally. Moreover, it includes its factory goodies.

If you’re the type of collector who only has eyes for the best, then this watch is for you!