Richard Mille RM 55-01 Manual Winding with new ultra-light calibre RMUL4

0 0 Friday, 1 May 2026 Edit this post

Richard Mille has introduced the new RM 55-01 Manual Winding, a timepiece developed around a principle often associated with Antoine de Saint-Exupéry: true refinement comes not from adding more, but from removing everything unnecessary.

The result is a watch whose architecture has been reduced to essential mechanical functions, with each component positioned according to structural or technical purpose.

The model is offered in three case variations — Carbon TPT, Grey Quartz TPT and White Quartz TPT — each measuring 47.33 mm x 37.95 mm with a thickness of 10.75 mm.

These advanced composite materials combine low weight with strong resistance to shocks and scratches, while their layered surfaces give each version a distinct visual identity. The tonneau-shaped case retains the taut lines and curved ergonomics that define the Richard Mille silhouette.

At the centre of the watch is the new hand-wound Calibre RMUL4, an ultra-light movement weighing less than 5 grams.

Operating at 4 Hz (28,800 vibrations per hour) and delivering a power reserve of approximately 55 hours, it continues Richard Mille’s long-standing emphasis on lightweight engineering and openworked construction.

The choice of manual winding contributes to that objective by eliminating the mass of an automatic rotor, while also allowing an unobstructed view through the movement.

The calibre is built on a Grade 5 titanium baseplate, selected for its rigidity, corrosion resistance and low weight. Its surfaces receive a microblasted treatment with black PVD coating.

The going train is supported by three Grade 5 titanium bridges, finished with brushing and treated with Titalyt, an electrochemical oxidation process that increases surface hardness and resistance to wear while giving the metal a matte appearance.

As with many Richard Mille movements, the regulating organ is designed with stability and shock resistance in mind.

The free-sprung balance uses variable inertia adjustment through four movable weights rather than a traditional index regulator, improving long-term rate consistency. A stop-seconds mechanism is also integrated for precise time setting.

Energy is supplied by a twin-barrel system engineered to provide more consistent torque delivery over the running period.

By distributing energy through two barrels, pressure on internal components is reduced, contributing to smoother power transmission across the 55-hour autonomy.

The movement is secured inside the case by Grade 5 titanium spline screws and framed by satin-finished pillars with polished bezels.

Above it, rhodium-plated hands with microblasted surfaces sweep over a multi-part flange combining titanium, carbon fibre and steel, adding depth and contrast while preserving legibility.