Zenith’s latest release sees the Manufacture partner with Japanese independent watchmaker Naoya Hida & Co. for a new interpretation of the G.F.J. Calibre 135.
Building on the success of the G.F.J released in 2025 and again at Watches & Wonders this year, Zenith has brought together one of watchmaking’s most celebrated chronometer movements with independent watchmaker Naoya Hida & Co’s restrained and highly detail-focused design approach.
Limited to just 10 pieces, the G.F.J. Calibre 135 Double Signed with Naoya Hida & Co. is a pared-back and restrained version of the models we’ve seen over the last 18 months or so.
Rather than dramatically reshaping the watch, the collaboration introduces subtle refinements throughout, allowing the character of both brands to come through naturally. And for collectors familiar with Naoya Hida’s work, the influence is immediately recognisable.
A Refined Interpretation Of The G.F.J.
Speaking with Benoit de Clerck, Zenith CEO, earlier this year, he explained that the G.F.J is a continuing project that Zenith is very proud of, and given the reception both last year with the Lapis Lazuli 160th Anniversary Edition, and again this year with the Bloodstone and Onyx dials, it isn’t surprising that the Le Locle brand is doubling down on the collection.
The platinum case retains the same elegant proportions as the previous G.F.J. models, measuring 39.15mm wide and 10.5mm thick. The biggest changes come through the dial, where Naoya Hida’s appreciation for classical mid-century watchmaking is evident.
Crafted from solid silver, the dial features engraved markings completed using a traditional pantograph engraving machine. The Arabic numerals are individually hand-finished by Japanese engraver Keisuke Kano before being filled with blue Japanese urushi lacquer, creating a subtle sense of depth across the otherwise restrained layout.
The overall presentation feels clean and balanced, particularly through the carefully proportioned small seconds display and minimal text arrangement. Attention to detail extends to the hands as well. The hour and minute hands are CNC-machined from solid gold before being hand-polished, led by master watchmaker Kosuke Fujita, while the small seconds hand is finished in heat-blued steel.
While this isn’t the vibrant stone dials, there is a quiet luxury and elegance to the dial, especially when you think about the handcrafted techniques used. Nothing here feels excessive, which is precisely why the watch works so well, and for those who like an understated dial, the new Zenith G.F.J. hits the mark.
The Return Of A Legendary Chronometer Movement
At the centre of the watch sits the modern re-engineering of Zenith’s historic Calibre 135. We’ve covered this a fair bit last year when the G.F.J. was released, as well as our trip to Le Locle and the Zenith Manufacture and our in-depth discussion with both Zenith’s Head of Product, Romain Marietta, and Heritage Director, Laurence Boddenman. But for those who missed these, which I recommend you have a read after this article, then here is a quick backstory.
Originally developed in 1948 by Zenith’s Chronometry expert, Ephrem Jobin, the calibre 135 was designed specifically to compete in Observatory Trials – competitions that pitted the best watch Manufactures against each other to see which movements were the most accurate and reliable through a series of tests.
It was called the Calibre 135 due to the size of the movement being 13 lignes in size (30mm in modern metrics) and 5mm thick, which was significant as movements back then had to fall within this size limit to compete at the Observatory trials, for which the Calibre 135 was designed
It is the most awarded and one of the most accurate movements produced by the Manufacture. From 1950-1954 (inclusive), it won the prestigious Chronometry Awards at the Neuchâtel Observatory for those five years in a row. All up, the Calibre 135 collected a total of 235 chronometry prizes between 1949 and 1962, and for this reason, it is perhaps the most historically important movement for the Le Locle brand.
The calibre first returned in 2022 through a limited project involving restored vintage movements, most notably with the limited release in conjunction with Kari Voutilainen, auctioned via Phillips in association with Bacs & Russo, before becoming the foundation of the new G.F.J. collection released for Zenith’s 160th anniversary last year.
Visible through the sapphire caseback, the hand-wound Calibre 135 combines its original architecture with modern upgrades throughout. The movement beats at 18,000 vibrations per hour (2.5Hz), delivers a 72-hour power reserve, and incorporates a stop-seconds mechanism alongside shock-protected balance staff jewel settings.
Zenith has also retained several historically important elements of the movement, including the large variable inertia balance wheel with Breguet overcoil and Charles Fleck’s distinctive double-arrow regulator system. The finishing is equally impressive, with broad Côtes de Genève, hand-chamfered edges, and a dark ruthenium finish contrasted by gold-coloured engravings.
The movement is COSC-certified and regulated to an increased accuracy of +/-2 seconds per day, which is Zenith reinforcing the chronometer-focused philosophy behind the Calibre 135 from the very beginning.
A Collaboration Built On Shared Appreciation
Naoya Hida has spoken openly about his admiration for the Calibre 135 dating back to the 1990s, long before establishing his own brand. That appreciation comes through in the watch itself, where the focus remains on proportion, balance, and quiet detail, which is a slight departure from the more embellished models to date.
The three supplied straps continue the Japanese influence found throughout the watch. Buyers receive a Himeji Kurozan leather strap finished with urushi lacquer, a Kyoto-crafted Wagyu leather strap, and an indigo Japanese denim strap produced by Kaihara Denim in Hiroshima.
Final Thoughts
The G.F.J. Calibre 135 Double Signed with Naoya Hida & Co. will inevitably remain a very rare watch given its production of only 10 pieces, but the appeal of this release goes well beyond exclusivity. Given the first meeting and the relationship between Romain Marietta and Naoya Hida, and when you speak with Romain, he is a watch lover through and through, it isn’t surprising that this collaboration has come to fruition in this way.
This is a collaboration that feels genuine from both sides. Naoya Hida’s design language complements the Calibre 135 exceptionally well, bringing a quieter and more intimate character to one of Zenith’s most historically important movements. The “less is more” silver dial with hand-engraved numerals and indexes filled with blue urushi lacquer is perfectly complemented by the platinum case and straps.
Writing this article up, it dawns on you that this is another version of the Zentih G.F.J. that speaks to a different market altogether. It also shows another side of the watch, which we have not seen to date in the modern renditions. A perfectly elegant watch that is understated, but exudes luxury and refinement. If you know, you know!
Reference & Specifications
| Feature | Specifications |
|---|---|
| Reference | 40.1865-2.0135/01.C220 |
| Dimensions | 39.15mm case diameter x 45.75mm lug-to-lug x 10.5mm thickness |
| Case | 950 Platinum |
| Dial | Solid silver dial with the double signatures precision-engraved. Arabic numerals are hand-engraved and filled with blue Japanese urushi lacquer |
| Crystal | Flat sapphire |
| Caseback | Open sapphire caseback |
| Movement | Manual wind Calibre 135 with small seconds complication & COSC Chronometer certification, accurate to +/-2 seconds per day. Côtes de Genève with Ruthenium finishing |
| Power Reserve | 72 hours |
| Beat Rate | 2.5Hz / 18,000VpH |
| Water Resistance | 50m / 5bar |
| Strap | Delivered with three straps: Himeji Kurozan leather, Wagyu leather crafted in Kyoto, and Japanese non-stretch denim from Kaihara. Platinum pin buckle engraved with the G.F.J. initials |