The story goes like this: in 1975, a saturation diver from Kure City in the Hiroshima prefecture of Japan sent Seiko a complaint regarding the reliability of it’s existing line of professional dive watches. The complaint exposed some notable flaws in it’s existing design, most notably their "susceptibility to the absorption of helium gas, a component of the air mixture that saturation divers were enveloped in".
In response, Seiko’s engineers led by Ikuo Tokunaga, set out to make the perfect dive watch for professional saturation divers. Tokunaga spent five years developing the world’s most advanced diving watch, built for the tiny target market of offshore commercial divers. Nicknamed the “Tuna” because of it’s cylindrical slab of lugless casing, the resulting product was a marvel of modern engineering. It’s monocoque titanium case, L-shaped gasket, and unique shrouded design were all firsts in the industry. Case size: 50.5 mm!
The result was a watch that was impervious to helium gas penetration, and one that could withstand the pressure of massive depths up to 600m. It instantly became a modern classic for Seiko, and has been in continuous production for the last 42 years. |
|