When it comes to making ultra-thin watches, it’s hard to think of a more eminent name than Piaget. Self-proclaimed “Master of Ultra Thin”, the crafting of ultra-thin movements and cases has been a specialty of Piaget for over half a century now, starting with the Caliber P9 back in 1957. Remember, Piaget first started out as a movement manufacturer and supplier before creating its own branded watches. Out of the 35 movements the conceived and manufactured by the Piaget manufacture, 23 of those were ultra-thin calibers with 12 movements breaking records during the time of their release.

With their latest ultra-thin creation the Altiplano 900P, Piaget have once again reclaimed their title as the producer of the thinnest mechanical wristwatch in the world. And this time it looks like Piaget can hold on to that title for a very, very long time. While it might not have the thinnest movement, it is overall the slimmest mechanical watch, coming in at a mere 3.65mm in height. Thanks to the unique construction of the movement and the way it is integrated with the case, the 900P is so much more than just an ultra-thin wristwatch.

To understand how the 900P came to be, you have to look at how Piaget produces its components. Piaget has two manufacturing facilities in different regions of Switzerland. One is responsible for manufacturing movements, while the other specializes in case manufacturing. You could call it a collaborative effort of sorts, as the two separate yet synergetic manufactures had to find a totally new way of interpreting the ultra-thin watch. With the 900P this goes far beyond that just making the thinnest movement possible.

For one thing, the case back isn’t just a case back. To reduce the thickness of the case, Piaget had the ingenious idea of making using the case back as the mainplate of the movement. Not only does this mean that the movement cannot be removed from the case, it also implies that the movement is inverted, with the bridges on the dial side of the watch. This is the first time Piaget has incorporated the case back into the movement.

But that’s just the start of the 900P’s unusual construction. If you look closely you’ll notice that the dial is actually sunken and sits lower than the gear train bridge, and there’s a reason for that. To maintain the watch’s performance under high pressure where crystals deform, the hands and cannon pinion are positioned lower than the bridges, so if the crystal were to deform it would press on the wheel-train bridge without affecting performance.

To render the 900P even slimmer, the entire mechanism and hand-setting system is kept within the thickness of the balance wheel. This accounts for the off-centered dial. Typically, a wheel in your average watch movement measures around 0.20mm in thickness. In the 900P however, they go as thin as 0.12mm.

Aesthetically the 900P is a bit of a departure from what we’re used to seeing from Piaget, especially in the minimalist Altiplano line. It’s not a skeleton watch per se, though the way the dial is fitted onto (or should I say into) the movement means that most of the moving components are visible from the dial side.

For a watch that’s technically advanced but produced in more conventional materials, I was taken aback to see Piaget opting for a modern black/anthracite plating (on the original white gold version) that gives the watch an edgier “concept watch” look. This is probably why I find the watch so darn appealing. It’s almost paradoxical, as I tend to associate ultra-thin watches with minimalistic plain white or silver dials . That’s probably another reason why I find the 900P so alluring.

And just because it’s the slimmest wristwatch ever doesn’t mean the movement was compromised in the least. When fully wound, the movement has a power reserve of 48 hours, provided by a patent-pending suspended barrel hanging from a single bridge (it’s right under the three-spoke wheel at the lower-right side of the dial).

The level of hand-finishing is also noteworthy. The treated bridges are beautifully chamfered and polished on the edges, as are some of the larger wheels. The radial sunburst finish is carefully applied and made to appear as if extending from the recessed dial to the bridges.

So how does it wear? In all honesty I’ve never been a big fan of ultra-thin watches. While I do appreciate the art and complexity that goes into a watch or movement so thin, I find them a bit too formal for my tastes. That being said, the Piaget Altiplano 900P totally blew me away in person. The case diameter is only 38mm, though when trying it on I could’ve sworn it was at least 40mm. It must be the thin bezel and the fact that there’s so much to feast the eyes on. And needless to say, the 900P has no problem slipping under a cuff.

Aside from the main white gold version that took the watch world by storm (and which remains my personal favorite), Piaget also presented several other versions during SIHH 2014, such as this rose gold version with a silver-tone movement, taking on a more classical look as the wheels blend in with the bridges.

There’s also a white gold version with a brilliant cut diamond set bezel, retaining the same 3.65mm thickness as the non-jeweled gold versions.

Finally, there’s a Haute Joaillerie version that’s slightly thicker at 5.65mm. It features baguette cut diamonds on the bezel, as well as a slightly raised dial with 33 baguette diamonds. The sides of the case as well as the lugs are set with brilliant cut diamonds. Heck, even the screws on the bridges and wheel-trains are set with brilliant cut diamonds! While the Haute Joaillerie version loses out on slimness, it makes up for it with a more three-dimensional display.

In a time where it’s becoming harder and harder to find a groundbreaking, beautifully finished watch for under 6 figures, it’s easy to understand why I find the Piaget Altiplano 900P to be the most alluring watch thus far in 2014. With a price tag of around $26’000 for the non gem-set gold models, it’s certainly a lot of horological bang for the buck.

More information on www.piaget.com