In Greubel Forsey's modern catalog, the Convexe collection has become one of the most prominent examples of the brand's approach to watchmaking. Introduced in 2019, the Convexe case features a double-curved construction that follows the natural shape of the wrist and presents the movement as a sculptural object. The Balancier Convexe S² first appeared in 2021 with a highly openwork architecture that the brand describes as an “urban landscape,” with multiple levels, suspension bridges and dramatic depth revealing the large, tilted balance wheel.
In 2023, the brand offered 41.5mm S² in titanium and carbon, maintaining the concept while evolving the appearance and finish. Now the history of the S² reaches its final chapter. The brand presents two final versions of the Balancier Convexe S², one in black ceramic with red gold accents and the other in white ceramic, the most exclusive versions of the caliber before its production is definitively discontinued in 2026.
The double-domed Convexe case measures 41.5 mm across the case edge and maintains the profile that has become the hallmark of the collection. The case features sapphire crystals curved on both sides, a three-dimensional bezel with variable geometry and profiled lugs secured with visible screws. As you can imagine, despite its highly technical appearance, the watch sits comfortably on the wrist.
The black ceramic and 5N rose gold edition is all about contrast, volume and visual depth. The dark ceramic middle case frames the movement architecture, while the rose gold bezel and caseback provide warmth and a feeling of weight. In the white ceramic version, the monochrome case reveals the structure of the movement through light and shadow and supports the purity of the convex geometry.
As with most of Greubel Forsey's creations, the dial is essentially the movement, arranged on multiple levels and designed to reveal the mechanical function rather than conceal it. The hour ring is positioned high under the sapphire crystal, while the lower part of the watch opens to reveal the large inclined balance wheel. The polished steel hands are filled with Super-LumiNova and positioned on a suspended, arch-shaped bridge, a signature element of the S² design. The large inclined balance wheel at the bottom of the watch is the chronometric center and focal point of the design. Other indicators include the small seconds, positioned next to the balance wheel on a gold subdial, and a sector-style power reserve indicator integrated into the movement's layered architecture.
The watch is powered by Greubel Forsey's hand-wound caliber GF09XV, which consists of 301 components, including a 68-piece escapement platform for the brand's signature 30° inclined balance system, which is intended to improve chronometric stability by reducing positioning errors.
Power is supplied by two rapidly rotating coaxial barrels that rotate once every 3.2 hours and provide a chronometric power reserve of 72 hours. One of the barrels is equipped with a sliding spring to prevent excessive tension. The in-house balance wheel with variable inertia has a diameter of 12.6 mm and is equipped with six gold screws. It beats at 21,600 vibrations per hour and is equipped with a balance spring with a Phillips end curve and Geneva bolts.
As for the finishing, titanium bridges and main plates are matt finished and hand finished, with polished bevels and countersinks. The multi-stage suspension bridge is straight grained and polished, while the back of the movement features frosted bridges with polished edges and a gold plate engraved with a limited edition number. Areas that are rarely visible after installation receive the same attention.
Both final editions come on a hand-sewn, textured rubber strap, in black or white depending on the version, and close with a folding clasp made of titanium or titanium and 5N red gold. A three-row titanium bracelet with integrated fine adjustment is also available upon request.
Availability and price
These two ceramic models represent the final production series of the Balancier Convexe S² movement and are limited to just 11 pieces per edition. Production of the movement will finally stop in 2026 as Greubel Forsey gradually switches to a new generation of watches and mechanical developments. The price is on request. For more information, visit greubelforsey.com.
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