Limited Audemars Piguet perpetual calendar watches celebrate the watchmaker's 150th anniversary

As part of its 150th anniversary celebrations, Audemars Piguet has revealed a trio of new watches. And they don’t just look pretty, they represent a significant horological engineering achievement.

Audemars Piguet’s Royal Oak watches use the perpetual calendar complication, which keeps track of days and months, with a knowledge of how many days are in each month too.

It’s a low-adjustment kind of calendar, but its complexity means such perpetual calendar watches are typically of a larger stature.

Audemars Piguet’s latest are its first perpetual calendar timepieces at a 38mm scale, while casing thickness is a reasonable 9.4mm. Its other watches of this style typically have a 41mm scale.

Spot the differences

There are two internally distinct models in this fresh trio too. The stainless steel and rose gold Royal Oak designs have a simpler brushed metal bezel with screw head style decoration, where the green and gold Code 11.59 family watch bears additional outer dial numbering for the week of the year. It’s slightly thicker too, at 9.9mm.

This is likely because the two key styles have a different internal movement. The steel and gold Royal Oaks use Calibre 7136, the other Calibre 7138. Both boast a 55-hour power reserve, but the Calibre 7136 loses the week indicator.

Curiously, their water resistance ratings differ too. The Royal Oak duo are rated at 50M, the Code 11.59 30M.

We doubt too many would risk these on a scuba dive, though. The stainless steel Royal Oak and Code 11.59 watches are listed at £91,600, while the rose gold's price is available on request.

All three have 18K gold elements, though. In the stainless steel Royal Oak, white gold is used in the luminescent hour markers and hands. In the Code 11.59, 18K pink gold is seen in the casing wall and the strap clasp, as well as the hands and hour markers.

Its strap is "alligator" pattern leather, while all three have Sapphire Crystal casebacks and front protection.

While it’s borderline comical to suggest a smaller 38mm frame opens up a watch this expensive to a broader audience, it does give the series — and Audemars Piguet perpetual calendar designs as a whole — a refreshed appeal.

150 limited anniversary editions of the watches will be available, engraved to signify as such on the caseback.

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