Jean-Marc Fleury - FXR-4 Openwork
There are independent watchmakers who assemble movements. Then there are those who build them—from the bridges up. Jean-Marc Fleury falls firmly in the second camp, and his latest creation, the FXR-4 Openwork, offers something increasingly rare in contemporary horology: a completely in-house chronograph calibre that doesn't merely homage the legendary Lemania 2310, but fundamentally reimagines it for the 21st century.
The original FXR-4, launched in 2024, established Fleury's ability to recreate the legendary Lemania 2310's magic while solving its limitations. The FM04 calibre grew from 27mm to a more contemporary 32.5mm diameter—filling a 40mm case properly rather than swimming in it. The frequency increased from 18,000 to 21,600 vibrations per hour, yet power reserve expanded to 60 hours. Most significantly, Fleury integrated the chronograph driving wheel directly into the going train, placing both it and the fourth wheel under a single bridge—an architectural elegance Patek Philippe itself only achieved with the later CH 29-535.
The Openwork edition takes this foundation and performs radical surgery. A sapphire dial replaces the solid brass, revealing 279 components arranged in a choreography of German silver (maillechort) bridges treated with ruthenium-free NAC coating. The column wheel and horizontal clutch—those hallowed emblems of traditional chronograph construction—are no longer hidden behind solid metal but exposed to light and scrutiny. This is transparency as consequence of mastery: every chamfer, every satin-brushed plane, every mirror-polished screw head must withstand direct visual interrogation.
The case, crafted in Grade 23 titanium, speaks to Fleury's philosophy of performance engineering. This isn't the standard Grade 5 titanium common in watchmaking; Grade 23 offers superior biocompatibility and corrosion resistance—overkill for a 30-meter water-resistant dress chronograph, perhaps, but entirely consistent with a former Patek Philippe maker who spent years producing medical-grade precision components. At 40mm diameter and 12.8mm thickness, the proportions hit a sweet spot between vintage restraint and contemporary presence.
Technical Specifications
Case
Dimensions: 40 mm diameter x 12.8 mm thickness
Material: Grade 23 titanium; crown and pushers in stainless steel
Crystal: Sapphire crystal with anti-reflective coating
Caseback: Sapphire display back with anti-reflective coating
Water Resistance: 30 meters
Dial
Type: Openwork sapphire
Hands: Bercé-main hour and minute hands; satin-brushed running seconds hand; polished pointer date hand; red lacquered chronograph hands
Movement
Calibre: FM04 Openwork (in-house, manual winding, NAC coated)
Functions: Hours, minutes, seconds, chronograph with date and day/night indicator
Dimensions: 32.5 mm x 6.5 mm
Components: 279
Architecture: Column-wheel chronograph with horizontal clutch
Frequency: 21,600 vibrations per hour (3 Hz)
Power Reserve: 60 hours
Jewels: 26
Strap
Leather strap with stainless steel pin buckle
Price: HKD $545,000