The Greubel Forsey Balancier Convexe S² GF09XV marks the final chapter of this standout calibre. It is released in two versions, a black ceramic with 5N red gold, and full white ceramic, each limited to just 11 pieces, making them exceptionally exclusive. After five years of development, production of the movement will end in 2026, adding to its long-term collectability. Housed in a 41.5mm Convexe case, the watch is built around a 30° inclined balance wheel, combining strong chronometric performance with a distinctive, modern design. What sets the Balancier Convexe S² apart is how seamlessly the case and movement are designed together. The curved case follows the natural shape of the wrist, ensuring comfort while showcasing the depth of the openworked movement. Made up of 301 components, the calibre features a complex escapement and delivers a 72-hour power reserve through dual barrels. The balance operates at 21,600 vibrations per hour, while the finishing remains true to Greubel Forsey standards, with hand-finished titanium bridges, polished bevels, and careful detailing throughout, even on the parts you can’t see. The two editions offer contrasting aesthetics. The black ceramic and red gold version plays with depth and contrast, pairing dark tones with warm metallic accents for a bold, sculptural look. The white ceramic edition takes a cleaner, more technical approach, using light and shadow to highlight the movement’s architecture. Both retain the same functional layout, including suspended hours and minutes, small seconds, and a power reserve display. Together, they serve as the final and most refined expression of the Balancier Convexe S².