The Tri-Axial Tourbillon by Girard-Perregaux features a regulator on three separate axes. At its heart beats a traditional tourbillon. Its cage performs one rotation in one minute. It is integrated within a structure positioned on a second axis and performs a complete rotation in 30 seconds. Finally, both are inserted into a third system. The ensemble is placed on a third axis and performs one rotation in 2 minutes. The diameter of the ensemble comes to 13.78 mm.
With a total weight of 1.24 grams, the cage and the drive systems are made of steel. The support pillars are in titanium, or in pink gold to act as a counterweight where the kinetic balance required this. As for the balance, it integrates 16 pink gold adjustment micro-screws. It has an increased frequency of 3 Hz, or 21,600 vibrations per hour.
Displaying hours, minutes and a time reserve indicator, the new GP09300 mechanical caliber with manual winding measures 36.10 mm in diameter with a height of 16.83 mm. It comprises 317 components and has a minimum power reserve of 52 hours.
The Tri-Axial Tourbillon caliber remains absolutely faithful to the purest of traditions. The cage adopts the lyre shape that has been characteristic of Girard-Perregaux Tourbillons since the 19th century. The components are decorated and finished by hand with the greatest care. They present mirror-polished surfaces and perfect chamfering (especially on a number of inward angles which are particularly difficult to finish). The gear train is circular-grained and the sides are satin-brushed. On the case-back, the eagle, the symbol of the manufacture since 1897, is engraved and a plaque in the arrow shape of the Tourbillon with Three Bridges' iconic bridges bears the individual number of each piece. This shape is also found on the emblematic gold bridges also visible on the back of the movement.
Constructed on several levels, the dial of the Tri-Axial Tourbillon presents a wide aperture at 9 o'clock that reveals the regulation system. At half past one, a silver dial with Clous de Paris motif presents numerals and hour markers in pink gold. It is encircled with an applique in pink gold and a black flange that displays the minutes numerals in white. Starting at the center of the watch, the power reserve indicator follows a curve that ends at 6 o'clock. Designed graphically to form an array of circles and curves, the dial presents concentric, regular stripes in the areas that have been left empty. Girard-Perregaux's initials gleam in pink gold at 11 o'clock.
Crafted from pink gold, the case respects the design codes of Girard-Perregaux's Haute Horlogerie collection with a beveled bezel, a rounded case-center and lugs that narrow out elegantly towards the exterior. The superior sapphire crystal presents a spectacular construction. At 9 o'clock, a domed sapphire crystal, designed to highlight the tourbillon's three axes, is applied to the main crystal, which is first pierced to the required diameter. A toric-shaped sapphire crystal is also integrated into the side of the case at 9 o'clock in order to show this fascinating spectacle from another angle. Finally, the case-back, which is screwed and transparent, reveals the entire movement and, in particular, the satiny circular bridge engraved with the words "Tri-Axial" that supports the differential of the tourbillon system.