The Artisans de Genève Zinal Challenge is a one-of-a-kind personalization inspired by the frozen landscapes of the Swiss Alps.
Commissioned by a private client and based on a Rolex Cosmograph Daytona reference 116520, the project transforms the familiar 40 mm chronograph through extensive skeletonization, transparent sapphire components, flame-blued details and a manually wound interpretation of the Rolex calibre 4130.
Completing the composition is an exclusive transparent vulcanized rubber strap developed by Rubber B specifically for the watch.
Rather than interrupting the visual clarity of the sapphire dial, bezel and exposed movement, the transparent strap allows the entire timepiece to preserve one uninterrupted design language. It remains one of the most distinctive private collaborations in Rubber B’s history.
The Zinal Challenge was commissioned by a private client. Artisans de Genève is an independent workshop and is not affiliated with or authorized by Rolex SA. Rubber B is also an independent company and is not affiliated with Rolex SA.
Quick Answer: What Is the Artisans de Genève Zinal Challenge?
The Zinal Challenge is a privately commissioned Artisans de Genève personalization based on the Rolex Daytona reference 116520.
The watch features a transparent sapphire dial, polished sapphire bezel, skeletonized manually wound calibre 4130, flame-blued components, a titanium case back and a one-off transparent Rubber B strap. The project was inspired by the Zinal Glacier and the monochromatic, ice-covered landscapes of Switzerland’s highest peaks.
The Zinal Challenge Specifications
| Feature | Artisans de Genève The Zinal Challenge |
| Base watch | Rolex Cosmograph Daytona reference 116520 |
| Case diameter | 40 mm |
| Case material | Stainless steel |
| Dial | Polarized transparent sapphire |
| Bezel | Polished transparent sapphire |
| Hands | Polished and flame-blued with rhodium-plated centers |
| Base movement | Modified Rolex calibre 4130 |
| Winding | Manual |
| Movement finish | Skeletonized, sandblasted and hand-beveled |
| Additional finish | Nickel-palladium treatment |
| Power reserve | Approximately 72 hours |
| Ratchet wheel | Beveled and flame-blued |
| Balance bridge | Beveled and flame-blued |
| Case back | Titanium |
| Strap | Exclusive transparent vulcanized rubber strap by Rubber B |
| Strap reinforcement | Integrated titanium insert |
| Project type | One-off private personalization |
The specifications published when the project was introduced describe a fully modified calibre 4130, sapphire dial and bezel, 72-hour power reserve and exclusive transparent strap created in collaboration with Rubber B.
Inspired by the Zinal Glacier
The name of the project refers to the Zinal Glacier in the Swiss Alps.
For the private client behind the commission, Zinal represented more than a geographic location. Its glacial surfaces, pale reflections and severe mountain environment became the aesthetic foundation of the watch.
Artisans de Genève interpreted this landscape through transparency rather than color.
The familiar black, white and metallic contrasts of the standard Daytona were replaced by sapphire, exposed mechanics and restrained blue details. The finished watch appears almost suspended between solid and transparent forms, reflecting the clarity and visual depth of ice.
The project was not designed as a conventional limited edition or commercial watch release. It was a personal commission created for private use, shaped around the owner’s connection to the Swiss mountain landscape.
The Rolex Daytona 116520 as the Foundation
The original watch selected for the personalization was the Rolex Cosmograph Daytona reference 116520.
Produced in stainless steel with a 40 mm Oyster case, the 116520 introduced Rolex’s in-house calibre 4130 to the Daytona collection. Its balanced case, screw-down chronograph pushers and recognizable three-register layout provided the technical foundation for the Zinal Challenge.
However, very little of the standard watch’s visual character remained untouched.
Artisans de Genève transformed the Daytona through:
- A skeletonized movement
- A transparent sapphire dial
- A transparent sapphire bezel
- Flame-blued hands and movement components
- Manual-winding conversion
- A titanium case back
- A bespoke transparent Rubber B strap
The objective was not simply to expose the mechanism. Every component had to contribute to the glacier-inspired composition.
A Sapphire Dial Designed to Disappear
The dial is one of the most technically demanding elements of the Zinal Challenge.
Created from transparent sapphire crystal, it allows the modified movement to remain visible from the front of the watch. The material was selected because it could provide the required clarity while preserving the structural organization of a traditional chronograph dial.
The counters use a polarized treatment, creating subtle contrast without placing an opaque surface over the movement.
Sapphire is extremely hard once finished, but it is also difficult and fragile during production. Shaping, drilling, polishing and finishing the material requires considerable precision. A minor error during machining can compromise the entire component.
The result preserves the recognizable Daytona register arrangement while allowing the calibre beneath it to become the dominant visual feature.
A Transparent Sapphire Bezel
The Zinal Challenge also replaces the original metal Daytona bezel with a transparent sapphire component.
Its tachymeter scale remains visible around the perimeter, preserving an essential element of the Cosmograph Daytona identity. However, the clear sapphire construction changes the visual weight of the watch.
A traditional Daytona bezel creates a strong border around the dial. The transparent bezel of the Zinal Challenge reduces that separation, allowing the dial, case and strap to appear as parts of one continuous structure.
The bezel was polished to create a clear, ice-like surface. Its transparency also permits light to move differently around the edge of the watch, strengthening the connection with the glacier that inspired the project.
A Skeletonized Calibre 4130
The technical center of the Zinal Challenge is the extensively modified Rolex calibre 4130.
Artisans de Genève dismantled and skeletonized the movement, removing material to reveal components that would ordinarily remain concealed. The bridges and movement architecture were cut, sandblasted and beveled by hand.
Skeletonization must preserve a careful balance. Removing too little material limits visibility; removing too much can affect structural integrity. The remaining bridges must continue to support the movement while becoming part of the watch’s visual composition.
The monochromatic nickel-palladium finish reinforces the glacial theme. Rather than introducing several contrasting metals, the treatment creates a restrained mechanical landscape of pale and silver-toned surfaces.
From Automatic to Manual Winding
The standard Rolex calibre 4130 is an automatic chronograph movement.
For the Zinal Challenge, the automatic winding system was removed. Artisans de Genève converted the movement into a manually wound mechanism and replaced the original winding architecture with a specially developed barrel system.
Despite the conversion, the modified movement provides an approximate power reserve of 72 hours.
The decision serves both mechanical and visual purposes.
Removing the rotor permits a clearer view of the movement through the back of the watch. It also encourages a more direct interaction between the owner and the mechanism, since the watch must be wound manually.
The conversion therefore transforms not only how the movement appears, but also how the owner experiences the watch.
Flame-Blued Details Against the Monochrome Movement
The Zinal Challenge is primarily defined by transparent and silver-toned materials. Flame-blued details introduce carefully controlled color.
The ratchet wheel and balance bridge were beveled and flame-blued. The central hands were also polished and flame-blued, with rhodium-plated centers.
These blue components provide contrast against the pale movement without overwhelming the design.
Their color recalls the blue shadows found beneath ice and within deep glacial formations. The treatment also connects the watch to traditional decorative watchmaking, where heat-blued steel has long been used for hands and movement components.
Each blue element has a functional place within the composition. The hands remain visible against the transparent dial, while the movement components guide the eye through the exposed calibre.
The Transparent Rubber B Strap
The transparent strap is not a secondary accessory to the Zinal Challenge.
It is the final component that allows the watch’s central design concept to continue beyond the case.
A conventional black, white or colored strap would have introduced a visual boundary at the lugs. The clear Rubber B strap allows the stainless-steel case, sapphire components and skeletonized movement to remain the principal focus.
Rubber B developed the strap specifically for the Daytona case used in the Zinal Challenge. The transparent vulcanized rubber construction contains an integrated titanium insert engineered to support the connection between the strap and watch.
This was not a standard-production transparent strap selected from an existing collection. It was created expressly for the private commission and remains Rubber B’s singular transparent design associated with the Zinal project.
Why a Transparent Rubber Strap Was Technically Challenging
Transparency creates challenges that do not exist with an opaque rubber compound.
In a conventional black or colored strap, the material can visually conceal much of the internal engineering. A transparent strap exposes every structural decision.
The internal insert, material consistency and case connection all become visible parts of the design. Imperfections that might remain hidden inside an opaque strap would be immediately apparent.
The Zinal strap therefore had to achieve several objectives simultaneously:
- Preserve a clear and consistent appearance
- Support the weight of the 40 mm chronograph
- Create a precise connection with the Daytona case
- Integrate a solid titanium reinforcement
- Remain supple around the wrist
- Continue the visual language of the sapphire dial and bezel
- Avoid distracting from the exposed movement
Rubber B’s product documentation describes the transparent strap as having been built specifically for the Daytona case and containing a titanium insert. It was manufactured in Switzerland as part of the collaborative Zinal execution.
The Titanium Insert
The titanium insert inside the transparent strap has both structural and aesthetic importance.
Rubber B integrated straps use solid inserts to stabilize the connection between the strap and a specific watch case. The insert houses the spring-bar channel and supports a secure, calibrated mount at the lugs.
Within the transparent Zinal strap, this insert becomes visible rather than concealed.
Its presence reinforces the industrial character of the watch and connects visually with the metallic movement components beneath the sapphire dial.
Titanium was particularly appropriate for the design because of its strength and relatively low weight. It provides internal reinforcement without introducing unnecessary mass to the strap.
The insert also demonstrates that the transparency of the strap was not intended to disguise its engineering. The structure becomes part of the visual result.
A Strap Created as Part of the Watch
The most important distinction is that the transparent strap was developed as part of the Zinal Challenge itself.
It was not a universal strap adapted to the watch after the personalization was completed. The case, sapphire elements, movement finishing and strap were considered as one complete composition.
The strap follows the Daytona case and continues the project’s themes of:
- Transparency
- Precision
- Swiss craftsmanship
- Material experimentation
- Mechanical visibility
- Monochromatic restraint
This approach reflects the philosophy behind model-specific strap development. A strap should account for the exact architecture of the watch rather than depend solely on a shared lug width.
For the Zinal Challenge, that principle became especially important. The strap had to support the watch physically while appearing to disappear visually.
The Only Transparent Rubber B Execution
Rubber B is recognized for integrated straps in black, white and a wide spectrum of permanent colors, as well as VulChromatic®, SwimSkin®, Velcro® and other specialized constructions.
The Zinal Challenge remains distinct within this history.
Its transparent strap was not developed as a conventional addition to the Daytona product line. It was a custom execution created exclusively to complete this private Artisans de Genève personalization.
Rubber B identifies “The Transparent Zinal” within its official collaboration archive, alongside other bespoke projects completed with Artisans de Genève and private clients.
Its rarity is therefore not based only on the color—or absence of color—of the material. It is defined by its inseparable relationship with one particular watch.
The Titanium Case Back
The rear of the Zinal Challenge continues the emphasis on mechanical visibility.
The project specifications identify a titanium back, while published images show the skeletonized manually wound movement through the rear of the watch.
Removing the automatic winding rotor creates an unobstructed view across the movement architecture. The flame-blued balance bridge and ratchet wheel become especially prominent from this perspective.
The use of titanium complements the internal titanium reinforcement of the Rubber B strap, creating a subtle material relationship between the watch and its attachment.
A Complete Study in Transparency
Transparent watches can easily become visual exercises without a coherent purpose.
The Zinal Challenge avoids that result by applying transparency consistently.
The sapphire dial exposes the mechanism.
The sapphire bezel reduces the visual boundary around the dial.
The openworked movement reveals its construction.
The rear display allows the manual-winding calibre to be observed from the opposite side.
The transparent Rubber B strap extends the same language beyond the watch case.
Each element contributes to the same concept rather than competing for attention.
The finished project does not simply display more of the watch. It creates the impression that the mechanism is suspended within the case, surrounded by surfaces inspired by ice.
Artisans de Genève and Rubber B
The Zinal Challenge forms part of a broader history of collaborations between Artisans de Genève and Rubber B.
Rubber B has developed straps for several privately commissioned Artisans de Genève projects, including:
- The Grand Bleu project
- The Zinal Challenge
- The Armstrong project
- The Barrichello project
Each strap was developed according to the identity and technical requirements of the individual watch rather than treated as a generic accessory.
The Zinal collaboration remains the most visually radical because the strap itself had to become transparent.
Is the Zinal Challenge an Official Rolex?
The underlying watch began as a Rolex Cosmograph Daytona reference 116520. However, the Zinal Challenge is an independent personalization carried out at the request of the watch’s private owner.
Artisans de Genève is not affiliated with or authorized by Rolex SA. The original manufacturer did not approve or participate in the modifications.
Artisans de Genève describes itself as an independent workshop that personalizes watches supplied by private clients. It does not manufacture or sell the original watches and performs its work independently of the watch brands.
The Zinal Challenge should therefore be described as:
An independently personalized Rolex Daytona 116520 by Artisans de Genève.
It should not be described as an official Rolex model, Rolex collaboration or factory-produced Daytona reference.
Was the Transparent Strap Sold to the Public?
The transparent Rubber B strap was developed specifically for the Zinal Challenge.
It should be presented as a bespoke collaborative execution rather than a conventional production strap available across the standard Rubber B collection.
The design’s relationship with the personalized case, titanium insert and transparent components makes it inseparable from the original project.
Collectors seeking a Rubber B strap for a standard Rolex Daytona should select from the current reference-specific Daytona collection and confirm compatibility using the complete watch reference.
Frequently Asked Questions
What is the Artisans de Genève Zinal Challenge?
The Zinal Challenge is a privately commissioned personalization based on a Rolex Daytona reference 116520. It includes a skeletonized manually wound movement, sapphire dial, sapphire bezel and transparent Rubber B strap.
What inspired the Zinal Challenge?
The project was inspired by the Zinal Glacier and the ice-covered landscapes of the Swiss Alps. Its transparent and monochromatic materials were selected to reflect the appearance of ice and mountain light.
Which Rolex was used for the Zinal Challenge?
The project began with a stainless-steel Rolex Cosmograph Daytona reference 116520 with a 40 mm case.
Is the Zinal Challenge an official Rolex model?
No. It is an independent personalization commissioned by a private client and completed by Artisans de Genève. Rolex SA did not authorize or participate in the project.
Is the Zinal Challenge movement automatic?
No. Although the original calibre 4130 was automatic, Artisans de Genève removed the automatic winding system and transformed the movement into a manually wound calibre.
How long is the power reserve?
The modified manually wound movement provides approximately 72 hours of power reserve.
Is the dial made from sapphire?
Yes. The watch features a transparent polarized sapphire dial and a polished transparent sapphire bezel.
Who made the transparent strap?
Rubber B developed the exclusive transparent vulcanized rubber strap in collaboration with Artisans de Genève for the Zinal Challenge.
Was the transparent strap designed for any Daytona?
The strap was built specifically for the Daytona case used in the Zinal project. It should not be presented as a universal rubber strap.
Does the transparent Rubber B strap contain an insert?
Yes. Rubber B’s published product information identifies a titanium insert within the transparent strap.
Can the transparent strap be purchased?
The strap was a bespoke execution associated with the private Zinal Challenge commission. Standard Daytona owners should consult the current Rubber B collection for reference-compatible production straps.
Is the strap made from vulcanized rubber?
Yes. Rubber B identifies it as a transparent Swiss-Made vulcanized rubber strap developed specifically for the Daytona case.
Final Assessment
The Artisans de Genève Zinal Challenge is defined by a rare level of design consistency.
The sapphire dial and bezel reveal the hand-finished movement. The conversion to manual winding permits an unobstructed view through the back. The flame-blued hands and bridges introduce controlled color into an otherwise monochromatic construction.
The transparent Rubber B strap completes the project by allowing its visual language to continue beyond the watch case.
Developed exclusively for this private commission, the strap was not simply attached to the finished watch. It was engineered as part of the Zinal Challenge itself, with a titanium insert, reference-specific construction and a clear material that demanded precision throughout every visible detail.
The result is a watch inspired by glacial transparency in which the movement, case, sapphire elements and strap function as a single composition.
It remains one of the most technically and visually distinctive collaborations between Rubber B and Artisans de Genève—and the singular transparent expression within the Rubber B collaboration archive.
This personalization was commissioned by a private client. Artisans de Genève is an independent workshop and is not affiliated with or authorized by Rolex SA. Rubber B is an independent company and is not affiliated with Rolex SA. Rolex, Cosmograph Daytona and related trademarks are the property of Rolex SA. Artisans de Genève and Rubber B are responsible only for their respective independent work described in this article.
Follow Us on Instagram
