A Limited Edition Model Celebrating the 50th Anniversary of a Masterpiece of Mechanical Divers Watches

To commemorate the 50th anniversary of this masterpiece, it is now available as the "1968 Mechanical Divers Re-creation Design SBEX007."

For the design recreation, the original sharp and massive one-piece case structure has been reproduced using Zaratsu polishing (※1), while the adoption of a newly developed L-shaped glass gasket upgrades the water resistance from 300m air diving to 300m saturation diving.

Furthermore, the material of the strap, which features the original unique pyramid-pattern, has been changed from vinyl chloride to reinforced silicone, and the glass material from inorganic glass to sapphire crystal, endowing it with the aesthetic appeal and durability befitting a modern luxury timepiece.

The movement is the "8L55," a mechanical movement exclusively for dive watches. Its high-speed vibration of 36,000 vibrations per hour (10 beats per second) ensures stable accuracy. The mainspring and balance spring are made of a proprietary alloy. Despite its 10-beat frequency, it achieves a practical power reserve of approximately 55 hours (when fully wound) from a single barrel. Manufacturing is handled by the Shizukuishi Watch Studio (※2), which is responsible for high-end mechanical watches.

(※1) Zaratsu Polishing
A surface finishing technique that uses a rotating flat lapping plate with an abrasive material (such as sandpaper) instead of polishing compound. By pressing the case against this rotating plate, it creates flat surfaces and smooth curves without distortion.

(※2) Shizukuishi Watch Studio
One of Japan's leading specialized studios for high-end mechanical watches, established in 2004. Located within Morioka Seiko Instruments (Shizukuishi, Iwate Prefecture), it handles everything from parts manufacturing to assembly.

Page02.Another Model Celebrating the 50th Anniversary of Mechanical Divers

Another Model Celebrating the 50th Anniversary of Mechanical Divers

And another model celebrating the 50th anniversary of the 1968 mechanical divers is the "Deep Forest SBDX021." The deep green of the dial and bezel, characteristic of this model, is inspired by the lush, deep forests of "Yakushima," which nurture beautiful seas.

The waters around Yakushima, a UNESCO World Natural Heritage site and Japan's first, are known for their exceptional clarity and biodiversity due to ocean currents, making them one of Japan's premier diving spots.

The deep green bezel ring, which echoes the dial, uses zirconia ceramic, known for its scratch resistance and corrosion resistance. The stainless steel case and bracelet are treated with SEIKO's proprietary surface finishing technology, Diashield (※3).

Lumibrite (※4) is applied not only to the hands and indices but also to the bezel markers (from the ▽ mark to 20), which are primarily used to measure elapsed time during dives, enhancing visibility underwater and in low-light conditions.

(※3) Diashield
A proprietary surface finishing technology developed by SEIKO to protect the watch's original beautiful luster and finish from everyday scratches and minor abrasions.

(※4) Lumibrite
A phosphorescent paint that absorbs and stores light from sunlight or artificial sources in a short time (approx. 10 minutes: 500 lux or more) and emits light for a long duration in the dark (approx. 3-5 hours).