Monochrome Watches
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Bulgari Unveils The New World’s Thinnest Mechanical Watch, The 1.80mm Octo Finissimo Ultra

1.8mm of Swiss watchmaking innovation and Italian elegance.

| By Xavier Markl | 7 min read |
Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

The Bulgari Octo Finissimo collection is, without a doubt, one of the most striking watch creations of the last decade. An impressive saga turned the Roman Maison into the master of ultra-thin mechanical watchmaking. In just a few years, the brand has topped one record of thinness after the other. This remarkable streak of record-breaking ultra-thin watches was saluted with the Aiguille d’Or, the top prize at the 2021 Grand Prix d’Horlogerie de Genève, awarded to the Octo Finissimo Perpetual Calendar. But Finissimo cannot be reduced to a technical feat. In a class of its own, the collection also encapsulates elegant, disruptive Italian design… Still, one record was missing for Bulgari to be the uncontested master of ultra-thin. That of the thinnest mechanical watch. And as all good sagas need a climax, it is time for us to discover the spectacular Octo Finissimo Ultra and its 1.8mm thin profile…

In its relentless search for absolute slenderness, Bulgari has earned an impressive series of world records:

Bulgari Octo Finissimo entire collection 8 world records
The Bulgari Octo Finissimo entire collection, with the 8 world record watches.

There was one record missing in Bulgari’s quest, that of the thinnest mechanical watch, a record held by Piaget with the Altiplano Ultimate Concept. Back in 2018, Piaget had smashed a record previously held by Jaeger-LeCoultre (3.6mm) with this 2mm incredibly-thin watch. But Bulgari has pushed the limits of ultra-thin even further. At a spectacular 1.80mm, the Octo Finissimo Ultra is now the world’s thinnest mechanical watch ever created. It is 10% thinner than the Piaget Altiplano Ultimate Concept, which at that level of development is quite something! In other words, it is thinner than a 10 cent of Euro coin (1.93mm) or about as thin as a quarter dollar coin (1.75mm).

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Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

To achieve this exceptional feat, no fewer than three years of development were needed for Bulgari who teamed up with movement designer and producer Concepto in La Chaux-de-Fonds.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

From a design perspective, the Octo Finissimo Ultra retains all the codes of the collection with its signature matt monochromatic grey look. It comes in a 40mm case with an integrated bracelet with an “invisible” folding clasp matching the thinness of the case. The movement layout is also in line with the collection’s cues with two separate counters for the hours and minutes, and the seconds display directly on the fourth wheel at 6 o’clock. The watch feels almost surrealistic. The mechanism on full display creates a certain sense of depth, but its profile is truly unbelievably thin.

Reinventing Everything

Naturally, such a technical achievement requires pushing the limits of ultra-thin manufacturing, trimming down the components to the limits of feasibility and working with the most extreme tolerances. It also requires out-of-the-box thinking, with a complete reengineering of the entire watch, reimagining each component, its architecture and its functions.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

This is what leads Fabrizio Buonamassa Stigliani, Bulgari’s Product Creation Executive Director, to state that “the challenge of this eighth record was the most difficult to overcome since we had to break the rules not only in terms of movement design but also of the case, the caseback, the bracelet and the folding clasp. To achieve this degree of thinness, you not only have to review your way of thinking, but you must also draw upon a wide range of skills, play with multiple materials and adapt to a multitude of new constraints. In this sense, the Octo Finissimo Ultra is unquestionably the ultimate complication in this vast field of possibilities represented by ultra-miniaturisation.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

To begin with, and as was the case with the Piaget Altiplano Ultimate Concept, the caseback also serves as the movement base plate. However, the Piaget case/movement plate was a one-piece component which is not the case here. Indeed, the caseback and the case middle of the Bulgari Octo Finissimo Ultra are bonded together. The bezel is screwed from the back of the watch. On the material front, the case middle and the bezel are made of sandblasted titanium while the caseback and main plate assembly is fashioned out of ultra-rigid tungsten carbide, a particularly hard and ultra-resistant alloy of carbon and tungsten to ensure the overall rigidity.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

The ultra-thin crystal (0.30mm) is glued to the bezel. It rests on two silicone pads placed on screws (visible at the periphery of the barrel at approx. 3 o’clock and 6 o’clock) to preserve all functions in the event of a shock.

On the Bulgari Octo Finissimo Ultra, the movement components are therefore integrated directly into recesses machined into the case-back. The idea is to avoid having different layers in the watch architecture, taking advantage of the entire surface of the watch, re-arranging and building all functions in the same horizontal plane.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

In this perspective, the function and the design of different components had to be completely reimagined. One of the starting points was to use a regulator type display with separate time indications. Naturally, this allowed Bulgari to avoid using superimposed hands to keep the watch thinner… and from a style perspective, it creates an 8-shaped display (appropriate for a collection called Octo) with the hours and minutes dials.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

Always with the idea to build functions in the same horizontal plane, a standard crown for winding and setting the watch could not be used with such a thin watch. Bvlgari opted for two horizontal knobs placed on each side of the case – one for winding and the other for time setting. Each features a ratchet wheel to allow winding and setting in one direction only. The winding knob is unprotected while the time setting knob comes in between two protectors to avoid inadvertent operations. In addition, the small click wheel prevents backward rotation and with it, the mechanism requires a certain force to be operated. A differential gear mechanism is used to handle time-setting without disturbing the gear train.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch
The barrel ratchet wheel is so thin that the engraving of the QR code pattern on its surface involved additional engraving on the other side to avoid any deformation.

The barrel had to be completely redesigned too. To maintain a substantial power reserve (50 hours despite the thinness of the watch and the 4 Hz frequency), the barrel of the Bulgari Octo Finissimo Ultra features an oversized diameter. Still, you need to maintain a certain thickness for the mainspring. To do so, the barrel arbour is not rotating in a hole in the main plate. Instead, its pivot is slid to a u-shaped notch fixed onto the main plate while three rollers drive the rotation.

The oscillator incorporates a flat spring. It has not index and gold adjustment weights. It could not feature a conventional anti-shock device. Instead, the variable inertia balance is held in between flexible bridges that will deform in the event of a shock. One integrates the stud holder. The entire regulator module, with its two flexible bridges included, is only 1.13mm thick!

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

A total of eight patent applications have been filed for this Bulgari Octo Finissimo Ultra. They relate to the watch glass assembly, the barrel structure, the oscillator module, the differential display, the modular structure, the bracelet, the bimetal case middle-mainplate/caseback, as well as the Bvlgari Singvlarity technology.

A Digital Gateway

Last, if the QR code engraved on the barrel looks quite cool, it is also the gateway for an exclusive dedicated digital ecosystem that will be unveiled when the first Octo Finissimo Ultra hits the market in a few months’ time. Each of the ten owners of the Bulgari Octo Finissimo Ultra will receive an exclusive NFT artwork guaranteeing the authenticity of the watch and the link to its owner.

Bulgari Octo Finissimo Ultra - World's Thinnest Mechanical Watch

Availability & Price

The Bulgari Octo Finissimo Ultra (reference 103611) kicks off with a limited edition of 10 pieces as a nod to the 10th-anniversary of Octo. The price is set at EUR 400,000. Hats-off to Bulgari and all the people involved in this development for creating this record-thin Octo and for pushing the limits of the ultra-thin watch.

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3 responses

  1. Very clever packaging to squeeze everything into such a thin space producing two ridiculously small dials and looking a complete mess.

  2. Prohibido estornudar frente al cristal, alto riesgo de fractura por demasiado dinero. Ya lograron el record, ahora vendanlo!

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