Watch

The Genesis of Precision: Formex FX01 Micro-Rotor Movement

Jun 29, 2026, 6:04 PM

Formex, a brand previously known for utilizing reliable automatic movements from suppliers like Sellita and ETA, has embarked on a new chapter by introducing its first in-house manufacture movement. This strategic shift addresses the inherent design constraints that often come with relying on third-party calibers, which, despite their quality and chronometer certifications, can limit a brand's ability to innovate freely in terms of watch dimensions, layouts, and functionalities. To overcome these limitations and achieve groundbreaking designs, Formex sought a partnership with Horage, another prominent company based in Biel/Bienne, renowned for its expertise in developing and manufacturing advanced watch movements.

The collaboration between Formex and Horage is a testament to their shared philosophy of innovation and pushing technical boundaries within the Swiss watch industry. While Formex, through its parent company Dexel and dial manufacturer Cadranor, excels in crafting cases, bracelets, and dials for esteemed watch brands, Horage is a leader in movement development, creating cutting-edge calibers and technologies for its own watches and for select partners. This synergy led to the birth of the Formex Caliber FX01, a customized version of Horage’s esteemed K2 micro-rotor platform. This new movement has enabled Formex to create the exceptionally slim Aria Manufacture Chronometer, boasting a case height of just 6.9mm – a feat impossible with traditional third-party movements like the Sellita SW200-1 due to their conventional winding assembly architecture.

The Formex Caliber FX01, derived from Horage's K2 micro-rotor, showcases impressive technical specifications, including a 30mm diameter and a mere 2.9mm thickness. Its micro-rotor design integrates the automatic winding mechanism at the same level as the gear train, contributing to its slender profile. Despite the historical perception of micro-rotors having lower winding efficiency, the FX01 leverages Horage's optimized System-K engineering, a tungsten oscillating weight, and a highly efficient mainspring to deliver a remarkable 10 hours of power reserve from just one hour of wear. Furthermore, the 25-jewel movement operates at 25,200vph and offers a 72-hour power reserve, featuring silicon components for its balance spring, pallet fork, and escapement, ensuring anti-magnetism and reduced friction. A notable innovation is Horage's flexible gear train component, making its debut outside of Horage's own watches in the FX01. This technology eliminates hand backlash during time setting by maintaining constant tension, resulting in incredibly precise minute hand adjustments. Beyond its technical prowess, the FX01 also boasts a distinctive visual identity, developed by Formex, featuring galvanic black gold plating, laser-textured surfaces, and hand-beveled edges, moving away from traditional finishing techniques to reflect a modern aesthetic. Each FX01 movement is COSC-certified, guaranteeing exceptional timekeeping accuracy within -4/+6 seconds per day.

This pioneering micro-rotor movement signifies a monumental leap for Formex, opening avenues for an expanded range of horological creations. The collaboration with Horage, facilitated by their close proximity in Biel/Bienne, fosters a dynamic environment for future joint ventures. The Formex Caliber FX01's debut in the Aria Manufacture Chronometer, a limited founder's edition of 100 pieces priced at $7,900 USD, underscores the brand's commitment to innovation and elevated watchmaking, offering a compelling blend of advanced engineering and unique aesthetics.

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