The Audemars Piguet Royal Oak ref. 15400 is the largest Royal Oak ever made with an over-sized case with a diameter of 41 mm. This fantastic reference —also available in rose gold— is a clear result of the continuous evolution of the Royal Oak and the manufacture's constant forward thinking. 

Since its launch in 1972, the Royal Oak has gone through several design modifications including at least 12 references in 39mm, 12 in 36mm, 15 in 33 mm and even a rectangular Royal Oak ref. 6005. Today, the Royal Oak continues to embrace its core values just like it did 40 years ago regardless of its size. For some Royal Oak purists, bigger means betraying the original Jumbo. We have to admit that it took us a good year and months to come around; however, we can say with confidence that ref. 15400 is just as good.

The Royal Oak 15400ST.OO.1220ST.02 is fitted with the same bracelet as the discontinued ref. 15300ST but with the new double folding clasp with Audemars Piguet dark gray inlays. A few of the 15300STs in the last batch ever made also bear this newer clasp.

The bracelet has the exact same construction and impeccable brushed finished like on the rest of the Royal Oaks but we noticed under our loupe that the grain inside the AP letters on the clasp of ref. 15400ST seems to have a different finish when compared to those on ref. 15300ST. It almost appears to have more of a machine finish with a mesh looking pattern inside the letters —see pictures below.     

The dial is one of our favorite parts of this new Royal Oak. The silvered 'Grande Tapisserie' with a double baton at 12 and the small AP logo are the perfect combination to make this dial a very well balanced one; nevertheless, we do feel that the date aperture is somewhat small for this larger watch. Also we noted that ref. 15400 comes with a new calendar font and that the date disc is no longer off-white—see a side-by-side picture of both watches below. Another downside is the limited luminosity of the dial at night, as the luminescent material applied to the markers and hands is thinner than on ref. 15300.

Something worth mentioning is that the markers on ref. 15400 have the perfect shape for light refracting purposes. They are slightly angled at the sides which, along with the more straight and taller over polished flange, create a symphony of light and color. The light refraction on this dial is highly superior to any other Royal Oak dial we have ever seen and it projects all hues from silver to white and off-white depending on the lighting conditions. 

This newer reference is also fitted with the Audemars Piguet calibre 3120 just as the discontinued ref. 15300. This movement provides a power-reserve of 60 hours when fully wound and it's one of the most accurate ever made.

Upon close inspection of the crown on both references, we noticed that the crown on ref. 15400 is thinner/flatter than on ref. 15300. The water resistance rating of this watch is identical to that of ref. 15300 at 50m making it perfectly suitable for showering, swimming and even snorkeling. 

Whether you consider yourself a Royal Oak purist or not, all we can tell you is that ref. 15400 won't disappoint you. This bigger Royal Oak is perfectly balanced and it has a fantastic wrist presence. Because of its larger construction, we think that it can take on the daily abuse even better than its other Royal Oak counterparts.

Lastly, we know what you are thinking and what you would like to know about the larger size. No, it's not that much bigger than ref. 15300 and believe it or not, it doesn't wear that much larger either.   

Sticker Price $16,900 USD. For more info click here.