GMT Quadruple Tourbillon

Driven by creativity, unafraid to break new ground, Robert Greubel and Stephen Forsey confirm their love of three-dimensional architectures with this exceptionally complex timepiece. This first edition in white gold, limited to 11 of the total 66 pieces, brings together a quadruple tourbillon and a GMT function with a spinning terrestrial globe that displays three time zones in addition to universal time. As a first innovation, in order to save space and reduce volume, the four tourbillons nest in pairs. A spherical differential averages the rate of the two regulators for optimal timekeeping precision. The second original mechanism is the GMT function, materialised as a miniature terrestrial globe that makes one full rotation in 24 hours. Turning the watch over reveals the perpetual circumvolutions of the tourbillons, inclined at a 30° angle, next to a third time zone indication with the names of world cities.