Name: SB10 JUMPING HOUR UNION JACK
Brand: SARTORY-BILLARD
SKU: SB10UJ
Price: 4800.00 EUR
Availability: InStock

Have you ever felt time ?

A watch with no dial. Instead, a cabochon becomes the face of the watch itself. Not hidden behind glass, but exposed to the touch. You don't just see the material. You can feel it.
For its tenth anniversary, Sartory-Billard unveils the SB10.

A watch born from the SB08 project presented in 2024. This concept watch explored an extreme architecture, combining multiple sapphire elements, advanced complications, and a radical vision of time display: a large aperture for the hours, a fluid reading of the minutes, and a central surface entirely freed from the traditional dial.

Its development involved a level of complexity and demands that did not align with the balance we were aiming for.

And yet, its core idea endured: to offer a clear, almost poetic reading of time, grounded in material.

“I couldn’t give up what made the soul of the SB08,” explains Armand Billard. “That large, highly legible hour display, the fluid minute reading, and above all, that open surface, a true blank canvas for creativity.”

The SB10 is that idea made possible, not a simplification but a distillation, true to the Sartory-Billard philosophy. As the brand’s first complication, it marks a significant milestone. A vision once tied to a million-euro project, now made accessible.

Union Jack

In this version, the cabochon is crafted from stainless steel and entirely decorated with a complex guilloché composition inspired by the Union Jack.

Rather than using colours or printed elements, the iconic British flag is reinterpreted entirely through engraving, textures and light.

Machined in Switzerland by our team (Horocraft.ch) in Sainte-Croix, the cabochon is built from a succession of straight and curved guilloché lines, with each section varying in direction, spacing, and depth. The base is first decorated with a fine Côtes de Genève finish before moving on to the guilloché stage.

The entire complexity lies in the transitions: every group of lines, representing one of the colours of the Union Jack, must connect seamlessly with the next in order to preserve the readability of the motif without disturbing the overall balance of the surface. Achieving this result required numerous trials and adjustments before finding the right rhythm between the different sections.

The final effect is constantly evolving. Light reacts differently across each area, revealing contrasts, reflections, and volumes that change depending on the viewing angle.

Touch reveals an entirely different dimension of the surface. The reliefs, grooves, and engraved areas can all be felt when the finger touches the cabochon. Certain sections appear sharper and more defined, while others feel deeper and more textured, giving the whole piece a sculptural and tactile presence.

The idea for the SB10 Union Jack emerged while preparing Sartory-Billard’s participation in Hands On Horology London 2026. The team wanted to create a piece connected to the city hosting the event, leading naturally to a reinterpretation of one of Britain’s most recognisable graphic symbols through the visual language of the SB10.

Rethinking the jumping hour

Jumping hour watches offer a unique mechanical spectacle: an instant, precise, almost theatrical change. Yet they are often difficult to read, with small apertures and compressed numerals.

The SB10 takes a different path.

At six o’clock, a wide opening reveals the hour on a sapphire disc. This aperture has been deliberately enlarged to ensure immediate legibility, a conscious and almost personal choice.

“I’m 50 years old, I need to read the time clearly.” says Armand Billard.

The numerals appear in an unusually large format for a jumping hour watch, nearly twice the size of those found on more traditional pieces. Designed specifically for Sartory-Billard by typographer Simon Schmidt, they balance modernity with timeless clarity.

A simple glance at the wrist is enough. Time reveals itself effortlessly.

Without hands

The SB10 features no hands.

Time is entirely displayed through two ultra-thin sapphire discs, approximately 0.2 mm thick, that seem to disappear into the light.

The hour disc jumps 30 degrees every 60 minutes, instantly revealing the next numeral. This creates a striking visual effect, almost cinematic, a precise moment, a shift, a beat, a pulse.

The minute disc, by contrast, moves continuously around the cabochon, creating a dialogue between jumping time and flowing time.

Two rhythms coexist: one discrete and punctual, the other smooth and continuous. This duality defines the character of the SB10.

Minutes in orbit

The minutes are indicated by a sapphire disc completing a full rotation every sixty minutes. Around the cabochon, a peripheral ring coated with Super-LumiNova BGW9 traces the passage of time.

A red marker moves along this luminous ring, indicating the minutes with precision and clarity.

But it is at night that the SB10 reveals another dimension. The ring glows in a vivid turquoise, forming a continuous halo around the cabochon. The light appears to float, suspended around the central material.

Time is no longer simply read, it becomes an atmosphere: a slow, silent, almost hypnotic rotation, a luminous circle in motion, a small celestial phenomenon on the wrist.

Between watchmaking and jewelry

The SB10 has no traditional dial. In its place, a cabochon: a polished surface borrowed from the world of jewelry, with no mechanical function.

This element becomes the centerpiece of the watch, mounted from the outside like a precious stone set onto the case, not to display time, but to give it presence.

Its surface captures light, but also invites the eye and the hand. The cabochon is not only meant to be seen, it is designed to be touched. Polished, crafted, sometimes textured, it creates a physical, almost instinctive connection with the watch.

The cabochon is not interchangeable. It is an integral part of the watch, forming a personal bond between the object and its owner, much like a piece of jewelry that evolves with time.

This is a watch to be looked at as much as it is to be touched, where material invites gesture, where the finger follows the surface to feel its relief and temperature.

The watch becomes a meeting point between the rigor of watchmaking and the freedom of material expression.

The mechanism

Beneath its apparent simplicity lies a coherent mechanical construction.

The SB10 is powered by the automatic La Joux-Perret G101A caliber, paired with a patented jumping hour module ensuring a precise and instantaneous change.

Both hour and minute discs are made of sapphire and housed within a 39.5 mm stainless steel case.

Every technical choice serves the same vision: clarity, coherence, and purpose.

Technical Specifications

Name: SB10 Union Jack
Reference : SB10UJ
Case: Stainless steel, 39.5 mm, alternating polished and brushed surfaces
Thickness: 11,5 mm
Lug to lug: 44 mm
Cabochon: Stainless steel
Movement: Swiss-made La Joux-Perret G101A automatic movement, 55-hour power reserve coupled with a patented jumping hour movement
Water Resistance: 80 Meters
Bracelet Options: Sartory-Billard rubber strap in navy blue, red or white. Logo pin buckle.
Price: 4800€ excl VAT on rubber strap

Deliveries expected in Q3 2026.
Limited Edition of 5 pieces.
Exclusively available through the website.

SB10 JUMPING HOUR UNION JACK

€4,800.00 EUR

SB10 JUMPING HOUR UNION JACK

€4,800.00 EUR

Shipping & taxes

European Union customers: VAT is included in the price at checkout. No additional charges upon delivery.

United States customers: prices are quoted DAP (Delivered At Place). The customer is responsible for any tariffs and import duties as determined by local authorities at the time of import.

Rest of the world customers: prices are quoted DAP (Delivered At Place). Any applicable VAT / GST and import duties will be collected by DHL or FedEx prior to delivery.