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Greubel Forsey Tourbillon 24 Secondes

High confidence

The rotation period is the specification and it is directly measurable with nothing but a second hand. Twenty-four seconds against a conventional sixty is a large and unmistakable difference, which makes this among the most straightforwardly verifiable claims in the high-horology part of the catalog. The 25-degree inclination and the 24-second period are not arbitrary: Greubel Forsey states them as the combination that tested best chronometrically, which is why they are quoted as exact figures rather than approximations and why an examiner can hold the watch to them.

Specifications

Movement manufacturer
Greubel Forsey
Frequency
21,600 vph (3 Hz)
Power reserve
90 hours
Winding
manual
Complications
Inclined tourbillon · Twenty-four-second rotation

Architecture

A manually wound caliber with a single tourbillon carriage inclined at twenty-five degrees and completing one revolution every twenty-four seconds rather than the conventional minute. Driven by three fast-rotating coaxial barrels. The cage comprises 86 components in low-density aerospace alloys and weighs 0.38g.

Authentication notes

  • MovementProbable

    Time it

    One revolution every twenty-four seconds, on a visibly inclined axis. Timing the carriage requires no equipment and settles whether the mechanism is what it claims to be; combined with the visible inclination it constitutes a complete functional identification.

References using this caliber

Provenance of this record

Sources & Evidence

Primary sourceManufacturer documentation

Greubel Forsey — invention documentation and caliber specifications

Greubel Forsey SA

Accessed
2026-08-19

Cited for

This referenceHigh confidence
View source

Last verified: Not yet reviewed