Following years of research and development, Greubel Forsey unveils its fifth Fundamental Invention: the Différentiel d’Égalité. The hand-wound watch features regulated driving force — steady distribution of power from the mainspring barrel — for enhanced precision throughout the 60 hours of power reserve. The spherical timepiece has an inclined fixed escapement (at a 30-degree angle) made of 71 parts that minimizes the effects of gravity. The brand’s first dead-beat seconds makes it easier to set the time more precisely. The movement includes a balance wheel stop and a seconds reset feature that is activated when the crown is pulled out. The 359-part movement sits inside a 44mm 18K white gold case with a domed sapphire crystal and sapphire caseback. The multilevel dial sports a sapphire hour ring, lacquered indexes, gold-engraved and lacquered small seconds, and power-reserve indication. Greubel Forsey continues its high horology design codes, with all pieces hand finished and polished. Each of the 33 pieces is hand-engraved with its individual number.