Patek Philippe Introduces the Annual Calendar Chronograph Ref. 5905/1A

A sports chronograph but not the obvious candidate.

A model often overshadowed by “hot” watches or more complicated ones, the ref. 5905 combines a pair of useful complications into an everyday dress watch, but it was previously available only in a conservative, luxe guise of precious metal case and classical dial colours. But now Patek Philippe is changing up the feel of the model with the Annual Calendar Chronograph ref. 5905/1A.

Now cased in steel and matched with a three-link bracelet inspired by the Aquanaut, the ref. 5905/1A retains the sectored dial found on earlier versions of the model, but now in olive green – the same shade found on the Nautilus ref. 5711/1A-014.

Initial thoughts

Patek Philippe’s opening act for the year was the Nautilus ref. 5711/1A with an olive-green dial (and with the option of a diamond-set bezel), an immediate hit that has become one of the most sought-after watches of 2021. The Nautilus was already hot, as all sports watches with integrated bracelets are, but bestowing the most fashionable colour of the year on the “final edition” of the Nautilus ref. 5711 escalated its desirability to the stratosphere. That bodes well for the ref. 5905/1A.

The ref. 5905/1A will be instantly attractive since it caters to current tastes. Its inevitable desirability will overshadow its intrinsic qualities (and also the accessible price), which is a bit of a shame.

While intriguing it is not, the ref. 5905/1A is a good-looking watch, and one executed in a practical material while offering useful functions. And because of its material, the ref. 5905/1A is affordable as such things go, at least at the retail price.

That said, models like this should help divert demand away from the sports watches like the Nautilus and Aquanaut towards models like the ref. 5905/1A that perform just as well as an everyday watch.


Annual calendar and chronograph

Launched in 2015, the ref. 5905 replaced the ref. 5960, which was the brand’s first first chronograph with annual calendar that was in turn introduced in 2006.

Despite being similar in function and layout, the ref. 5905 was more elaborate in style than its predecessor. Instead of having “pump” pushers, the ref. 5905 featured rectangular buttons that sat along a gently concave case flank.

And the ref. 5905 was clearly designed in the same style as its more complicated brethren, namely the refs. 5207 and 5208 uber-complications, which added to its appeal. But perhaps because of the similar styling, the ref. 5905 gained the recognition it should have as a practical, mid-priced complication.

The familiar twi-window calendar found on the refs. 5905, 5207, and 5208

But the new ref. 5905/1A instantly vaults the references to the top of many wish lists. It has all the attributes of a sports watch – steel case and bracelet, along with an olive-green dial – though it is not a sports watch strictly speaking (its water resistance is 30 m for instance).

The facelift of the model is rejuvenating and shows that a complicated watch can look good in casual dress, albeit with just the right combination of materials and colours.

On top of the green dial, the ref. 5905/1A also gets a steel bracelet. It’s a sporty, three-piece affair that’s similar to the bracelet found on the Aquanaut ref. 5167/1A. The design sets it apart from the “brick” bracelet found on the ref. 5960/1A, the brand’s first-ever annual calendar-chronograph in steel.

The ref. 5905 and its predecessor share the same movement, the CH 28‑520 that combines a flyback chronograph and annual calendar.

Notably, the chronograph is modern in construction in featuring a vertical clutch, which is both more durable and precise than a horizontal clutch, and also allows the chronograph to be run continuously with no impact on timekeeping. But its utility comes at the price of reduced visual complexity, since the clutch is hidden under the bridges.

That said, the annual calendar mechanism is dated, having been launched in 1996, though has been a reliable performer and improved since its introduction.

Key facts and price

Patek Philippe Flyback Chronograph with Annual Calendar
Ref. 5905/1A-001

Diameter: 42 mm
Height: 14.13 mm
Material: Stainless steel
Crystal: Sapphire
Water resistance: 30 m

Movement: CH 28‑520 QA 24H
Functions: Hours, minutes, annual calendar, and flyback chronograph
Frequency: 28,800 beats per hour (4 Hz)
Winding: Automatic
Power reserve: 45-55 hours

Strap: Steel bracelet

Availability: At both retailers and boutiques
Price: US$59,140; or 78,000 Singapore dollars

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