DOXA
SUB 300 Ti5 Professional 823.50.351.21

DOXA unveils the SUB 300 Ti5

Grade 5 titanium returns to the permanent collection.

Seven new expressions: Six iconic DOXA colorways, plus a radical WhitePearl
version with a dial entirely coated in Super-LumiNova®.

True as ever to the spirit of the SUB. COSC-certified chronometer.

Grade 5 titanium is back at DOXA

The return of Grade 5 titanium marks another stage in the evolution of the permanent SUB 300 collection. Used for the case, crown and screw-in caseback, the material combines lightness, strength and corrosion resistance to exceptional effect.

Around 40% lighter than stainless steel while offering greater mechanical strength, Grade 5 titanium makes the SUB 300 Ti5 noticeably more comfortable on the wrist — day to day and over prolonged periods of wear.

Its hardness makes it highly resistant to mechanical stress, while the metal’s exceptional inertness makes it naturally resistant to seawater, humidity, temperature fluctuations and particularly harsh environments.

Grade 5 titanium, however, is demanding to machine. It calls for specific manufacturing processes and specialized expertise. Bringing it back to the permanent collection means taking on that added complexity for a clear purpose: to explore what the material can bring to the SUB 300 without compromising what it has always been — a true dive watch.

Immutable fundamentals: legibility, versatility, reliability.

Beneath the domed, anti-reflective “glass box” sapphire crystal, all dive-related indications are coated with Super-LumiNova®, ensuring excellent legibility in all conditions. The iconic oversized DOXA orange minute hand remains the diver’s immediate visual reference. The SUB 300 Ti5 is powered by a COSC-certified Swiss automatic movement beating at 28,800 vibrations per hour (4 Hz) and delivering approximately 38 hours of power reserve.

The screw-down crown and screw-in caseback round off a package water-resistant to 300 meters (984 feet), providing more than enough safety margin for underwater exploration.

COSC: certified precision

Every SUB 300 Ti5 is powered by a Swiss automatic movement officially certified by the Contrôle Officiel Suisse des Chronomètres (COSC), the international benchmark for precision in watchmaking.

Each movement earns its certification individually, following several days of independent testing against particularly stringent chronometric criteria. Movements are tested in different positions and at several temperatures to verify consistent timekeeping across a range of conditions similar to those encountered in everyday use.

For a dive watch, that degree of precision matters. Robustness, legibility and water resistance are the foundations of a true underwater instrument, but reliable timekeeping is just as essential.

COSC certification across the entire SUB 300 Ti5 collection brings technical performance, long-term reliability and quality of execution together. It aligns with the philosophy DOXA established with the first SUB 300 in 1967: uncompromising dive watches with the precision to match the environments they were built to face.

The caseback

Every SUB 300 Ti5 features a screw-in caseback crafted from Grade 5 titanium for strength and water resistance. It follows the same functional logic as the rest of the watch, and one that has defined DOXA from the beginning: every component has a job to do, and doing it well never comes at the expense of quality.