CONCEPTPushing back the boundaries. Grand Seiko’s first mechanical diver's watch for saturation diving.

Designed to meet the most demanding challenges on earth, Grand Seiko’s Professional Diver’s watch combines both high accuracy and the reliability that the serious diver requires. It is designed for saturation diving to a depth of 600m.

With a titanium case, exceptional anti-magnetism, a high beat movement, a 55 hour power reserve and a construction that is designed to defy the elements, this is a watch that pushes back the boundaries of what a diver’s watch can deliver.

FEATURESA professional diver’s watch and the aesthetics of Grand Seiko

A new-look diver’s watch incorporating the aesthetics of Grand Seiko

Form and function in harmony

With a distinctive clean edges appearing in a complex polyhedron and a distortion-free mirror surface created by our experts using Zaratsu polishing. The case has the beauAll the characteristics of the aesthetics of Grand Seiko are here. The distinctive clean edges and distortion-free mirror surfaces that only Zaratsu polishing can achieve, the supreme legibility that does justice to the precision of the movement and the durability that only a true, vertically integrated manufacturer can deliver. As soon as you see this watch, you know that it is Grand Seiko.

The one-way rotating bezel, perfected.

The grooves on the rotating bezel ensure a firm grip even with thick diving gloves. The bezel has excellent operability with a unique non-slip knurled finish. Each groove is carefully finished, making it easy to grip, but polished to be pleasing to the eye. Luminous markers at every ten seconds ensure the legibility that brings safety to the deep sea diver.

Enhanced anti-magnetism

The dial is made of pure iron in order to protect the movement from the harmful effects of magnetism and delivers magnetic resistance of 16,000 A/m. In addition to safe and secure use during diving, every-day usability is also assured.

Components, built for long-term use

Every component is built to last, but all divers know that their watch needs regular maintenance, just like every other device on which his or her life may depend. This is why even the case, stem and crown are designed for secure servicing and even the bezel has a four-part design that makes for easy disassembly and re-assembly.

A bracelet designed expressly for diving

The bracelet has a sliding extension setting to accommodate pressure changes. Moreover, the use of high intensity titanium allows the links to be thick, strong and corrosion resistant while still light and easy to wear.

MOVEMENTCalibre 9S85: The work of the true manufacturer

The 9S85 high beat movement is designed, made, assembled, adjusted and tested at the Shizukuishi Watch Studio. This remarkable facility is home to all Grand Seiko mechanical watch production. Each movement is tested individually before being built into its case and protected by the L-shaped seals that the company invented to ensure impermeability to dust, water and helium gas.


Movement Calibre 9S85
Driving system Automatic with manual winding mechanism
Accuracy +5 to -3 seconds per day (under a static use)

Note: This accuracy is the result of measuring the loss/gain of the time for seventeen days before the inside movements of the watch are put in the case. The measurement has been done in the factory where temperatures or position of the movements are controlled.

Power reserve Approximately 55 hours
Vibrations 36,000 vibrations per hour (10 beats per second)
Jewels 37 jewels
Remarks Date display