At the SIHH 2018 Audemars Piguet showed off the RD#2, their second Concept watch. A prototype with a thickness of 6.30mm, it became the new record holder for the thinnest automatic perpetual calendar wristwatc. This was in large part thanks to the development of a new ultra thin movement, the Calibre 5133, which is an astonishing 2.89mm thin. Coming in a 41mm 950 Pt case with a matching bracelet, its blue dial was decorated in the classic Grande Tapisserie pattern.
Now, in 2019, the RD#2 concept has become a commercial reality, with the announcement of the boutique-only version, called the Royal Oak Selfwinding Perpetual Calendar Ultra-Thin ref. 26586IP.OO.1240IP.01.
As was the case with the RD#2, this new piece comes in a 41mm sized case with a thickness of 6.3mm. However, instead of platinum, its case is a mix of polished and satin-brushed titanium, with a polished 950 Pt bezel and bracelet that is satin-brushed titanium with polished 950 Pt links, and a titanium folding clasp. The screw-down crown is also titanium.
As mentioned, last year’s piece used a new movement. The Calibre 5133 of that piece is the same one used in this production model. With 256 parts, it beats at 19,800VPH and has a power reserve of forty hours. The ‘thinning’ of the movement was down by merging the perpetual calendar functions, into a single layer. This also lead to two new patents. The end-of-the-month cam has been integrated to the date wheel, and the month cam has been combined to the month wheel.
A notable change from the RD#2 is aesthetic. The Grande Tapisserie has gone, replaced by a cleaner blue satin-finished dial. In terms of Audemars Piguet’s Royal Oak Perpetual Calendar dials there has also been a tweak, with larger sub dials (always a good thing when it comes to dials with a lot of functions). The day/ night indicator is incorporated into the day of the week sub dial and is counter-balanced by the leap year indicator on the month sub dial. In the Concept model, the day/ night indicator was half blue and half white, whereas for this one, ‘N’ and ‘D’ are used.
The applied hour markers are white gold, and both they and the hands are lumed.
As mentioned, this new Royal Oak Selfwinding Perpetual Calendar Ultra-Thin is available only through Audemars Piguet boutiques, with the price on request.
POSTSCRIPT : If you are in the market for a blue-dialled perpetual calendar, this year is a good one for you, because there has also been the Vacheron Constantin Patrimony Perpetual Calendar Ultra Thin Blue Dial, and the Jaeger-LeCOultre Master Ultra Thin Perpetual Enamel White Gold.