ZENITH And Naoya Hida Revive A Golden Age Tradition With The G.F.J. Calibre 135 Double Signed

Some collaborations are born from marketing opportunities. Others emerge from a shared reverence for watchmaking history. The new G.F.J. Calibre 135 Double Signed by ZENITH and Naoya Hida & Co. firmly belongs to the latter category. Limited to just ten pieces worldwide, the watch is more than a meeting of two respected names. It marks the launch of ZENITH's new Double Signed Program, an initiative designed to bring together independent watchmakers and the Manufacture's most historically significant creations. For its inaugural chapter, ZENITH could hardly have chosen a more fitting partner than Naoya Hida, whose understated, deeply considered approach to watchmaking has earned him a devoted following among collectors. At the heart of this collaboration lies one of horology's most celebrated movements: the Calibre 135.

The Movement That Defined Precision

Within ZENITH's rich watchmaking history, few movements command the same level of respect as the Calibre 135. Developed during the golden era of observatory chronometer competitions, it remains the most awarded movement in the Manufacture's history and is widely regarded as one of the finest expressions of precision watchmaking ever created. Its modern revival began in 2022 when ZENITH restored ten original Calibre 135-O competition movements from the 1950s. Meticulously refurbished by master watchmaker Kari Voutilainen, those ultra-exclusive timepieces reintroduced collectors to a legendary calibre that had long achieved near-mythical status.

Three years later, during ZENITH's 160th anniversary celebrations, the Manufacture once again brought the movement into the spotlight by re-engineering it for the launch of the G.F.J. collection, named after founder Georges Favre-Jacot. The latest chapter now sees the movement interpreted through the lens of one of Japan's most respected independent watchmakers.

A Meeting Of Minds

The collaboration was sparked by an encounter between Romain Marietta, Chief Product Officer of ZENITH Watches, and Naoya Hida in the latter's Tokyo workshop. Their shared appreciation for vintage watchmaking, historical chronometers and timeless design quickly evolved into a creative partnership. Founded in 2018, Naoya Hida & Co. has built its reputation on an uncompromising pursuit of classical watchmaking values. Every detail, from typography to proportions, is carefully considered, resulting in watches that embody quiet sophistication rather than overt spectacle. For Hida, the project carried particular significance. The Japanese watchmaker first encountered the Calibre 135 in the 1990s and has spent decades studying and admiring the movement. The opportunity to reinterpret the G.F.J. therefore represented not merely a collaboration, but a deeply personal exploration of a calibre that has long inspired him.

For seasoned collectors, double-signed watches occupy a special place in watchmaking history. Traditionally created through partnerships between manufacturers and influential retailers or collaborators, these watches have become highly prized symbols of shared heritage and craftsmanship. With the launch of the Double Signed Program, ZENITH aims to revive this tradition for a contemporary audience. The concept is built on a simple belief: iconic designs should continue evolving through creative dialogue. Each future collaboration will invite independent watchmakers to reinterpret the G.F.J., bringing fresh perspectives while remaining faithful to the spirit of the original. The Naoya Hida edition serves as the first expression of that philosophy.

Japanese Restraint Meets Swiss Precision

Housed in an elegant 39.5mm platinum case, the watch subtly incorporates design cues from Naoya Hida's acclaimed NH Type 1 and NH Type 2 models. The dial, crafted from solid silver, exemplifies the Japanese watchmaker's minimalist aesthetic. Every marking, including the signatures of both ZENITH and Naoya Hida & Co., is engraved using a traditional pantograph engraving machine.

The three Arabic numerals receive special attention. Each is individually hand-finished by renowned Japanese engraver Keisuke Kano before being filled with deep blue Japanese urushi lacquer. The result is a remarkable sense of depth and texture that rewards close inspection. The hands are equally meticulous. The softly rounded hour and minute hands are milled from solid gold using ultra-precise CNC machining before being hand-polished under the direction of master watchmaker Kosuke Fujita. Completing the display is a heat-blued steel small seconds hand. The overall effect is one of extraordinary restraint proof that true luxury often lies in subtle details rather than dramatic flourishes.

The Legendary Calibre 135 Reimagined

Turn the watch over and the true star of the show comes into view. Visible through the sapphire crystal caseback, the manually wound Calibre 135 showcases the refined architecture that helped secure its legendary reputation. The movement features broad Geneva stripes, delicate hand-chamfering and a contemporary dark ruthenium finish accented by yellow gold-coloured markings.

Operating at 2.5Hz, the movement retains several characteristics associated with high-precision chronometry, including a large variable-inertia balance wheel fitted with a Breguet overcoil and Charles Fleck's distinctive double arrow-shaped regulator. While faithful to its historical roots, the calibre has been thoroughly modernised. It now delivers a 72-hour power reserve, incorporates a stop-seconds mechanism for precise setting, and features spring-mounted jewel settings that protect the balance staff.

Most importantly, every movement is regulated to an accuracy of +/-2 seconds per day and carries official COSC chronometer certification an impressive achievement that honours the Calibre 135's competition-winning heritage. The collaboration extends beyond the watch itself. Each of the ten pieces is delivered with three bespoke straps showcasing different facets of Japanese artisanal excellence. The first is crafted from Himeji Kurozan leather, a rare material produced through traditional tanning techniques and enhanced with multiple hand-polished layers of Japanese urushi lacquer. The second uses premium Wagyu leather, created by Kyoto Leather artisans using time-honoured methods. The third introduces a more contemporary touch, fashioned from deep indigo Japanese non-stretch denim produced by the renowned Kaihara Denim mill in Fukuyama, Hiroshima. A platinum pin buckle engraved with the G.F.J. initials completes the package.

A Collaboration Rooted In Passion

What makes the G.F.J. Calibre 135 Double Signed compelling is not simply its rarity or technical pedigree. Rather, it is the authenticity behind the collaboration. The watch reflects a genuine dialogue between two makers united by a shared appreciation for horological history, precision and craftsmanship. It is a project that honours the past without becoming trapped by it, demonstrating how legendary watchmaking traditions can continue to evolve through thoughtful collaboration. Limited to just ten pieces, the G.F.J. Calibre 135 Double Signed with Naoya Hida & Co. is destined to become one of the year's most coveted independent collaborations and a fitting debut for ZENITH's ambitious new Double Signed Program.