Ralf Tech
WRB Blue Ocean Automatic 39 mm - Stainless Steel Strap Limited Edition

Ralf Tech WRB Blue Ocean Ref. WRB-1203- 39 mm — Automatic — Water-resistant 200 m (ISO 6425) — Blue dial Super-Luminova BGW-9 — Limited edition 100 pcs. Pre-owned

For Aquatic Leisure, A decidedly pro spirit. A dive watch built to withstand anything.

Beneath the surface, when the light fades and the sea sets the pace, you quickly grasp the difference between an accessory and an instrument. The WRB Blue Ocean is designed for days that slip from water sports to scuba diving, when salt air dries on the skin and time is measured to the second. Its 39 mm size embraces any wrist, slides under a technical sleeve, and its matte blue dial stays readable as visibility drops. BGW-9 luminescence takes over—cool and crisp—so every marker remains visible in the blue.

On the history side, the WRB line first appeared in an operational context as French Military Watch , built for French Army divers delivered between October 2019 and June 2020. Public success followed swiftly with a second series, still in 39 mm, then broader “Metal” variations in 2023. The Ralf Tech WRB-1203 Blue Ocean belongs to this recent family: limited edition of 100 pieces, steel case, navy-blue dial and “heavy duty” metal bracelet. Our pre-owned example comes from this recent “Metal” generation, corresponding to the early years of the Ocean Metal version.

At the seaside or the pool, it’s a diver fully at ease in the water, yet compact enough for the city. The sport-chic look of the blue dial suits a white shirt as well as a neoprene suit; the positive, precise bezel rotation and night-time legibility are a reminder that we’re talking about a tool first.

Why buy from Mostra. Our Aix-en-Provence workshop inspects every watch, and supplies a certificate of authenticity and a 3-year Mostra warranty. In 2025, Mostra became The first RALF TECH Certified Technical Center dedicated to Ralf Tech's pre-owned watches: complete diagnostics, overhauls to the brand’s specifications, and adjustments done by the book. This watch is a limited edition of 100 pieces, delivered with a Mostra box, ready for new immersions.

Dates & production period. Initial commercialization of the WRB: 2019–2020 (military deliveries), second civilian series from 2021; the Ocean Metal WRB-1203 variant appears within the “Metal” extension confirmed in 2023. Our example corresponds to the early years of the Metal version (period 2023+). On the mechanical side, the RTA003 automatic movement runs at 21,600 vibrations/hour; it offers a power reserve of up to 44 h (in everyday use, allow about 40 h). The matte blue dial is brought to life by Super-Luminova BGW9 indexes, the shade that emits in blue for clear underwater reading. Protection is ensured by a 2.5 mm domed sapphire crystal—one of the thickest in its class—paired with a 120-click unidirectional bezel compliant with the ISO 6425 standard, and 200 m / 20 ATM water resistance validating real aquatic use.