The Calibre de Cartier Astrotourbillon (Reference: W7100028) is a highly ambitious masterwork of haute horlogerie, representing a landmark release as Cartier’s first uncoated titanium watch for men. Introduced in 2011 as part of the brand’s Fine Watchmaking Collection, this model was strictly limited to only 100 pieces worldwide.

  Unlike a conventional tourbillon that rotates on its own internal axis, the Astrotourbillon features an elongated carriage where the entire balance and escapement orbit the central dial once every 60 seconds.

• The Seconds Indicator: An off-centered balance bridge, meticulously shaped like an arrow, serves as the actual sweeping seconds hand as it circles the dial. 

• Ultra-Lightweight Engineering: To limit rotational inertia, the visible carriage is constructed from ultra-lightweight titanium weighing a mere 0.39 grams. A hidden platinum counterweight sits beneath the central dial to maintain perfect equilibrium.

• Feature	Details
  Reference Number	W7100028
  Movement	Cartier Manufacture Calibre 9451 MC (Manual Winding)
  Components & Jewels	192 parts, 23 Jewels
  Frequency	21,600 vibrations per hour (vph)
  Power Reserve	Approximately 48 hours
  Case Material	Raw, brushed, and polished Grade 5 Titanium
  Case Dimensions	47 mm diameter
  Dial Design	Silvered guilloché with multi-tier framing and classic Roman numerals
  Hands	Blued-steel sword-shaped hands
  Crown	Octagonal titanium crown set with a faceted sapphire cabochon
  Case Back	Exhibition sapphire crystal case back
  Water Resistance	30 meters (3 ATM)
  Strap & Buckle	Black alligator leather with an adjustable folding deployment clasp