Patek Philippe Regulator with Annual Calendar Ref. 5235 Swiss Watches

The new Patek Philippe Regulator with Annual Calendar (Ref. 5235) is the first automatic watch with micro-rotor design from the highly respected Swiss watchmaking brand that successfully combines two complications in a single timepiece.




The task of creating a regulator wrist watch with an annual calendar complication doesn’t seem to be especially challenging. However, there are very few brands that successfully accomplished the mission.

Most of timepieces that feature such a combination of functions tend to sport bloated, hard to grasp layouts that somehow defeat the idea behind a regulator watch: in theory, it must be a highly legible device without numerous indicators screaming for attention, getting in each other’s way.

For Patek Philippe, which is known for the superb legibility of its timepieces, the mission wasn’t that difficult.

Patek Philippe Regulator with Annual Calendar Ref. 5235 automatic wrist watch

They simply (or so it seems) copied and pasted elements of design from their other watches and created a masterpiece that will without a doubt become a subject of countless case studies on various courses of industrial design.

As you can see on the photos above and below, the new watch sports rather standard regulator-style layout.

There is a centrally positioned minute hand that sweeps effortlessly along the blue transfer printed minute track and a pair of sub-dials at 12 and 6 o’clock showing hours and seconds respectively.

The day of week and month indicators are aptly placed between 10 and 11 and 1 and 3 hours respectively, while the small date aperture is placed at 6 o’clock, inside the subsidiary seconds indicator.

As simple as it could be. Also, very efficient.

Patek Philippe Regulator with Annual Calendar Ref. 5235 (front view)

To do the trick, however, the Swiss engineers had to seriously rework their well-known PP Cal. 240 automatic movement.

The first of all, they completely reworked the going train in order to reduce friction (and thus making it less prone to wear) and increasing the energy efficiency of the caliber.

Its escape wheel, the balance spring, as well as the lever of the Pulsomax escapement are now crafted not from a metal alloy, but from an anti-magnetic, shock-resistant, non-corroding, and lubrication-free Silinvar material, which is based on silicon.

To make the movement even more efficient, they equipped it with a reworked micro-rotor, which is made of solid gold and is 0.3 mm thicker than the base version.

Patek Philippe Regulator with Annual Calendar Ref. 5235 (side view)

As a result, the new watch sports 25 percent better power reserve (minimum 60 hours of continuous operation against 48 hours guaranteed for the Cal. 240,) while beating at a 10 percent higher speed of 23,040 vibrations per hour.

The base caliber is very simple in its design (it is normally used to power Patek Philippe’s dressy two-handers.)

So, in order to equip it with the annual calendar complication, it was equipped with a bespoke module that added around 1.3 millimeters to its overall diameter, almost 2.5 millimeters to its maximum height, and increased the parts count from modest 181 to more impressive 320 components.

The whole assembly, which is called Caliber 31-260 REG QA is placed inside a humble white gold case that features a very entertaining combination of mirror-polished (the chamfered bezel and the transparent case back with a sapphire crystal) and satin-finished (case-band) surfaces.

Patek Philippe Regulator with Annual Calendar Ref. 5235 (transparent case back)

Only 40.5 millimeters in diameter, it is less than 11 millimeters in height, which further emphasizes its role of an object of the difficult to learn art of inconspicuous consumption.

No funny stuff here: you can always wear such a timekeeper for a royal wedding without risking raising a regal eyebrow or two.




The list price for the new Patek Philippe Regulator with Annual Calendar (Ref. 5235) is yet to be announced*, but you would better be ready to pay at least €20,000 for this piece of understated beauty.

See also: Patek Philippe Triple Complication Ref. 5208P

Patek Philippe Regulator with Annual Calendar Ref. 5235 (Caliber 31-260 REG QA, front view)

Patek Philippe Regulator with Annual Calendar Ref. 5235 (Caliber 31-260 REG QA, rear view)

* UPDATE ON PRICE: The ref. 5235 will be first available with MSRP of $53,500.

Photos: Patek Philippe

Patek Philippe Regulator with Annual Calendar Ref. 5235 automatic wrist watch specification

Price: $53,500 (MSRP)
Movement: Automatic, Micro-Rotor, Caliber 31-260 REG QA, based on PP Caliber 240 movement, 23,040 vph, 29 jewels, 320 parts, Silinvar components, in-house, Swiss Made
Movement decoration: Geneva stripes, Patek Philippe Seal, micro-rotor in solid gold
Functions: Regulator hours, minutes, seconds, date, month, day of week
Power reserve: 60 hours
Case material: White gold
Bezel material: White gold
Crown material: White gold
Case shape: Round
Bezel shape: Round, chamfered
Case size: 40.50 mm
Lug width: 20.00 mm
Case height: 10.65 mm
Dial: Grey, vertical satin finish
Numerals: Arabic, blue, transfer printed
Hour markers: Blue
Hands: Blued steel
Water resistance: 30 meters
Strap: Natural Alligator leather strap with square scales, matt night-blue, hand-stitched, 16 millimeter prong buckle crafted from 18-carat white gold with signature “Patek Philippe” engraving
Crystal: Sapphire
Case back: Sapphire


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