GREUBEL FORSEY - Double Tourbillon Technique

Press kits

Double Tourbillon Technique

Double Tourbillon 30°, Hours and minutes display, Outer Tourbillon 4-minute rotation indicator, Inner Tourbillon 60 Second rotation indicator, power-reserve indicator.

Patented Movement
Movement dimensions 
• Diameter : 38.40 mm
• Thickness : 12.15 mm

Number of parts 
• Complete movement : 385 parts
• 2 Tourbillon cages : 128 parts
• Weight of the two cages : 1.17 g

Number of jewels 
• 43
• Olive-domed jewels in gold chatons

Power reserve 120 hours

• Four coaxial series-coupled fast-rotating barrels (1 turn in 3.2 hours), equipped with a slipping spring to avoid excess tension
• Gold nickel-palladium finished cover with relief engraving Balance wheel Variable-inertia with white gold mean-time screws (10.70 mm diameter)

Frequency 21,600 vibrations/hour

Balance spring 
• Phillips terminal curve
• Geneva-style stud

Main Plates Frosted nickel silver, polished bevelling, black chromed finish
Bridges Frosted nickel silver, polished bevelling, nickel-palladium finish, gold nameplate
bearing the watch number

• Involute circle profile
• Conical gearing with corrected profile

Inner Tourbillon Inclined at a 30° angle, 1 rotation per minute

Outer Tourbillon 
• 1 rotation in 4 minutes
• Hand-bevelled and openworked cage pillars
• Solid gold counterweight

• Hours and minutes
• Small seconds
• 4-minute Outer Tourbillon rotation indicator
• 120-hour power reserve on a sector

Case material and finishes 
• In 5N red gold, white gold or platinum with convex sapphire crystal
• Transparent back with convex sapphire crystal
• Raised polished engraving of the name of the Invention on a hand-punched background
• Gold security screws
• Nameplates with text screwed to the sides
• Three-dimensional lugs secured with screws
• Hand-engraved individual number

Case dimensions 
• Diameter : 47.50 mm
• Thickness : 16.84 mm

Water resistance of the case 3 ATM - 30 M - 100 FT

Crown Gold with engraved and black lacquered GF logo

• Sapphire hour markers
• Small seconds and power-reserve indicators in gold

• Hours and minutes in gold
• Small seconds, Power reserve (red triangles)
• Sapphire 4-minute indicator

Strap Hand-sewn black, brown, dark blue, grey or burgundy alligator leather with gold folding clasp, engraved with the Greubel Forsey logo