====== Greubel Forsey Nano Foudroyante ======

{{wst>image_cr|Greubel Forsey|Nano Foudroyante}}
{{wst>image_cr|Greubel Forsey|Nano Foudroyante back}}

**Nano Foudroyante** is a luxury Wristwatch by [[Greubel Forsey]].

In October [[2025]], Greubel Forsey presented the first official limited edition of its Nano Foudroyante: a groundbreaking timepiece that is the result of years of research and has now matured beyond its origins in Experimental Watch Technology (EWT). 

At the heart of this timepiece lies a disruptive idea: nanomechanics – the control of energy at the nanojoule scale inside a mechanical movement. This paradigm shift enables the Nano Foudroyante to operate its eponymous [[complication]] using just 16 nanojoules per jump, compared to 30 microjoules in traditional designs – a reduction by a factor of 1,800.

The complication divides each second into six segments using a lightweight, red-treated hand that rotates once per second, driven directly by the oscillations of the 3 Hz balance wheel. There is no traditional gear train; instead, a minimalist series of low-inertia wheels efficiently distributes energy through the movement.

The timepiece features a hand-wound [[flyback]] with 2 patents, totaling 428 components (including 142 for the tourbillon cage). Despite this complexity, the movement measures just 31.60 mm in diameter and fits within a 37.90 mm [[white gold]] case – Greubel Forsey’s most compact ever.

With this model, Greubel Forsey wins the ‘Mechanical Exception Watch Prize’ at the [[Grand Prix d'Horlogerie de Genève]] [[2025]].

<WRAP ud ud_mod>
**Reference:**
  * Nano Foudroyante

**Movement:**
  * [[Manual winding]] [[manufacture movement]], 21,600 A/h
  * [[Tourbillon]] 
  * [[Flyback]]
  * 2 patents
  * 428 components (including 142 for the tourbillon cage)
  * [[Power reserve]] 40 h

**Case:**
  * [[White gold]]
  * Ø 37.9 mm, H 14.34 mm
  * [[Sapphire crystal]] domed and transparent caseback

**Dial:**
  * Gold dial finished in [[rhodium]] with a blue minute track
  * Hands in blued steel with matching cannon pinions

**Functions:**
  * Hours, Minutes, Seconds
  * [[Tourbillon]], [[flyback chronograph]]
  * Nano mechanism sixth of a second

**Bracelet:**
  * Rubber strap with [[pin buckle]]

**Price:**
  * 502’200 CHF (2025)

**Limitation:**
  * 22 pieces
</WRAP>

{{tag>Watch_models Watches_with_tourbillon Chronographs Greubel_Forsey_models}}