hether in a plane cockpit or on a diver’s wrist, a central challenge for any watchmaking instrument has always been a display that glows in the dark to offer the best possible readability. Since the 1930s, various luminescent materials have been used to coat the hands, numerals and indices on timepieces intended for professionals, starting with the military – whether pilots or combat divers. With tritium and radium shelved due to radioactivity, Super-LumiNova is now the predominant material when it comes to achieving luminescence.

While every watch across the Bell & Ross collections displays the time even in the dark, some models go even further. This is the case for the brand’s Lum pieces, making direct reference to luminescence.

Bell & Ross launched its Lum line in 2017 with the BR 03-92 HoroLum, followed a year later by the BR 03-92 NightLum, both of which featured exceptional luminescence on the numerals, indices and hands. In 2019, the BR 03-92 Full Lum was launched, this time with a dial covered entirely in Super-LumiNova, with a contrast effect that highlighted key elements for maximum readability.

With the year 2020 came the first appearance of the BR 03-92 Grey Lum, emitting a particularly intense green glow reminiscent of landing strip lights, followed by the BR 03-92 Diver Full Lum, with a dial featuring different shades of light green and pale yellow luminescence. In 2021, the torch was passed to the vintage limited edition BR V2-94 Full Lum, showcasing the same double luminous effect. Finally, in 2022, the BR V2-92 Full Lum was released, featuring the ultra-luminescent dial in a 3-hand version.

Continuing the tradition of aeronautical heritage and the brand’s iconic “round within the square” visual signature, in 2022 the BR-X5 added a new chapter to the Bell & Ross BR 05 range launched in 2019. In its design, style and technical features, the BR-X5 takes its place as a superlative BR 05: the BR-CAL.323 calibre, a prestigious manufacture movement designed by Kenissi, raises the BR-X5 collection to the heights of precision with a power reserve of approximately 70 hours, while the architecture of its multi-component case prioritises purity and radicality, resistance and lightness. Now, Bell & Ross is completing its high-end line with its new model, the BR-X5 Green Lum. In its concept as much as in its design, the piece reflects the desire to innovate and dare to be different.

Bell & Ross has chosen to take things a step further and explore a new avenue of creative expression. To this day, the concept of luminescence has been applied to the hands, numerals, indices and dial of the models, on this new watch, it is the 41mm case that glows in the dark in a spectacular way, with a composite material developed specially for Bell & Ross: LM3D.

For the first time, the maison’s manufacture collection is venturing out onto planet Lum. For the structure of this new version of the BR-X5, lightness comes first on the multi-component case, which alternates LM3D and grade 2 micro-blasted black DLC titanium in a multi-layer assembly.

Cut from a block of DLC-coated grade 2 titanium, the case housing the mechanism is inserted between two shields made from a photoluminescent composite material, LM3D, made of quartz fibres that diffuse a powerful green luminescence. In the dark, the entire case glows, highlighting the dial’s indications: hours, minutes, seconds, date and power reserve. Beyond its watchmaking function, with this innovation, the new 500-piece limited BR-X5 GREEN LUM series achieves the rank of one-of-a-kind conceptual art object.

TECHNICAL SPECIFICATIONS

Movement:

• Calibre BR-CAL.323. Manufacture. Automatic mechanical. Approximate power reserve of 70 hours.

Functions:

• Hours, minutes and seconds. Date window at 3 o’clock and power reserve indicator at 9 o’clock.

Case:

• 41 mm wide. 12.80 mm thick. Container in Grade 2 microblasted titanium with DLC (diamond-like carbon) finish. Upper and lower inserts in green luminescent fiberglass composite. Fixed bezel in Grade 2 microblasted titanium with bezel insert in luminescent composite. Screw-down crown and crown guard in Grade 2 titanium. Case-back in Grade 2 microblasted titanium with smoked grey sapphire crystal with anti-reflective coating. Case-back with oscillating weight.

Dial:

• Matt black. Applique indices filled with black varnish. Skeletonised Super-LumiNova®-covered hour and minute hands. Black flange with 60-minute scale with green marking.

Crystal:

• Sapphire with anti-reflective coating.

Water-resistance:

• 100 metres.

Strap:

• Black openworked rubber.

Buckle:

• Folding. Steel with DLC (diamond-like carbon) finish.