The thinnest Overseas ever made arrives with a movement seven years in the making. Calibre 2550 measures just 2.4 mm—a fraction thinner than the legendary 1120 it succeeds—yet delivers 80 hours of power reserve through an architecture that required reinventing the self-winding mechanism from the ground up. It debuts in 950 platinum, a first for the Overseas collection, in a case that comes in at just 7.35 mm thick. For a sports watch, that is a remarkable proposition.
The Overseas Self-Winding Ultra-Thin arrives as a limited edition of 255 individually numbered pieces in 950 platinum—a first for the collection. The alloy used is not standard: it incorporates 5% copper and gallium, then undergoes thermal hardening to achieve 2.7 times the scratch and shock resistance of conventional platinum 950. At 39.5 mm in diameter and 7.35 mm thick, it is the thinnest Overseas ever made.
Things to Know About the Watch
The salmon-lacquered dial with sunburst satin finishing references a platinum-and-salmon pairing from the Maison's 1940s archive, a historically grounded choice that reads as quietly confident rather than nostalgic. Three tool-free interchangeable straps are included: platinum bracelet, beige rubber, and dark beige nubuck-touch alligator.
With its refined, almost minimalist aesthetic, the timepiece features a sunburst satin finished salmon-lacquered dial, complemented by a velvet-finished peripheral minute track.
The Movement
It took seven years to develop the new Vacheron Constantin calibre 2550. This new automatic movement equipped with a micro-rotor is the direct successor to the legendary calibre 1120, the 2.45 mm self-winding movement introduced in 1968 that effectively defined the ultra-thin category for decades. The new calibre comes in 0.05 mm thinner at 2.4mm—a marginal gain that required fundamental architectural rethinking.
Three innovations make it work together: a bidirectional platinum micro-rotor integrated directly into the mainplate; a suspended double barrel in which two stacked, inverted barrels share a single post, eliminating the barrel cover and the ratchet wheel; and a five-wheel single-level gear train, two wheels of which run on ball bearings. The result is an 80-hour power reserve from a movement that is 30.6 mm in diameter. The finishing is executed in full Geneva tradition with circular graining on the mainplate, Côtes de Genève on the bridges, snailing on the upper barrel drum. Integrating the micro-rotor directly into the mainplate provides a significant gain in thickness.
Integrating the micro-rotor directly into the mainplate reduces the thickness significantly. To optimize winding efficiency, the bi-directional micro-rotor it is crafted from 950 platinum, one of the densest metals, and it only measures 15.5 mm in diameter.
Summary & Price
The Overseas Self-Winding Ultra-Thin makes a measured but significant argument: that the sports watch category has no inherent conflict with the pursuit of slenderness. Calibre 2550 is the evidence. This new watch is available exclusively through Vacheron Constantin Boutiques.
Sticker Price Upon Request. For more information on Vacheron Constantin, click here.
