By Davosa

These days watches that glow in the dark are nothing unusual. The dial and hands are charged by the power of the sun or artificial light, ensuring they can be seen in the dark. Unfortunately this effect is not long-lasting: The luminance of most luminous materials fades noticeably after about 30 minutes. For everyday use and the average watch wearer this tends to suffice. The case is very different however for watches that are used for military purposes, in extreme conditions or in poor visibility underwater. In such conditions any reduction in luminance can prove disastrous, so luminous materials are used that keep the dial constantly bright and do not require an outside light source. A successful solution is to use luminous gas light sources: millimetre-thin glass tubes that are filled with tritium and can be applied to the hands and dial.

Swiss watchmaker DAVOSA uses these gas tubes to equip its popular Argonautic model series. This resilient divers’ watch with its helium valve and ceramic bezel is now available as an Argonautic Lumis Colour Automatic. 
Ten years’ constant luminance – thanks to extra-heavy hydrogen. Tritium is a colourless gas otherwise known as extra-heavy hydrogen. The name originates from the Greek word ‘tritos’ meaning third, and refers to the three components of the atom (3H). Tritium has been used for decades in all sorts of applications where constant, independent and long-lasting light sources are essential. On the dials of military watches you will often find a red, circular symbol with the notation ‘3H’ that refers to the use of tritium. In ‘civil’ watches, the abbreviation ‘T25’* denotes the same thing. In the past, luminous tritium was applied directly to the dial. Today’s watchmakers are more careful and fill the gas into fine tubes made from borosilicate glass, a highly resilient and ISO-certified glass used in chemical engineering. These Gaseous Tritium Light Sources (or GTLS) are not only exceptionally safe, they also guarantee the watch wearer at least ten years’ constant luminance – without any external energy source.



  • Gent's diver with self-winding movement - ETA 2824-2
  • Stainless steel case - 316L
  • Case dimensions: diameter 42,5 mm
  • Extra-thick sapphire crystal
  • Screw-in crown and back
  • 30 ATM (300 meters) water resistant
  • Manual helium valve
  • Black dial with tritium indexes and hands
  • Ceramic bezel - unidirectional and scratch resistant
  • Mesh steel bracelet with safety catch and diver's extension

Non EU customers: €723.33

EU customers: €868.00

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