The SEIKO Professional Diver's Watch Series

----A World-Class Achievement---


As part of its millenium celebrations, SEIKO is marketing reproduction models of some of itsbest-Known historical watches, combining the original design with modern technology.This "SEIKO Historical Collection" is being released in the Japanese domestic market at the rate of one model a month between June and December 2000. The final model in the seres will be the Professional Diver'w Watch, originally marketed in 1975 as the world's first titanium watch for 600-metre saturation diving by professionals. This provides a perfect opportunity to take a look at SEIKO's history and strategy in professional diver's watches.


Timeline Starting in 1965

SEIKO's first diver's watch was introduced in 1965. It combined state-of-the-art reliability and safety features and could be used to a depth of 150 metres.At the time, this market was a virtual monopoly

by Swiss manufacturers such as Rolex and Omega. Progress followed quickly, with a 300-metre model introduced in 1967, and a high performance version of it introduced in 1968. The progress continued until 1975 when the first ever titanium case model was introduced for 600-metre saturation diving.

A Letter from a Diver Leads to the 600-Metre Model

One day, a letter from a professional diver arrived at SEIKO's head office.This diver worked for long periods at great depths and often found himself for a week at a time living in a capsule at a depth of 365 metres. His diver's watches kept breaking down due to the great pressure of helium gas penetrating the case. SEIKO took the diver's plight to heart and started to develop a diving watch that would be water-tight and air-tight for helium gas, would resist the kind of pressure typical of great depths, would have dials visible in complete darkness, and would adjust to the wrist as adjustments are made to the pressure in diving suits. Most  importantly, it would also be resistant to a mixed-gas environment that included helium.

SEIKO worked to develop a watch that would surpass even the ISO standard requirements and produced an outstanding watch to meet the diver's needs.The outer casing alone lead to 20 new patents for the company. The resulting watch placed SEIKO   clearly in the global leadership position for

professional diver's watches.

Resistance to Helium Makes for Truly Professional Diver's Watch

The greatest characteristic of this watch is that it is resistant to helium. Most professional diver's watches let helium gas in and have to be specially processed to remove any residual helium to avoid explosions by using a helium gas escape valve.SEIKO's watch has been designed not to let helium in in the first place and therefore does not require this process.

Overall. the watch has much more resistance to lengthy immersions than standard models, and will continue to function perfectly normally, with no condensation inside the case, even after several months under water.

The use of titanium that has been treated with a ceramic finish greatly expands resistance to rust, and the dial has been designed to make the minute hand stand out very clearly.

Recognition Heaped upon the Titanium 600-Metre Diver's Watch

Other than being standard issue for the Japanese Maritime Self-Defense Force, SEIKO's diver's watches were also used by the US Navy during the 1970s. The watches were also rated very highly by professional divers and were in fact also used in other extreme conditions, including Everest and other Himalayan peaks, as well as both the North and South Poles.  In 1978, after being used for three months in -30 degrees C temperatures during an expedition of the North Pole, the 600-metre diver's watch was only about 5 seconds off the correct time. In 1983, the watch was tested at a depth of 1,062 metres by the Science and Technology Agency and performed without any problems in water resistance, pressure resistance and appearence.

In 1990, SEIKO exhibited at the annual show of the Diving Equipment Manufacturers Association  the world's first computerised diver's watch (Cal.M7) along with the 600-Metre Professional Diver's Watch for Saturation Diving. They were recognised to perform at the highest level when compared to Swiss equivalent models.

A Series That Catches the Explorer Spirit

The 600-Metre Professional Diver's Watch for Saturation Diving that was marketed in 1975 has since seen its mechanism changed to quartz,  and depth resistance increased to 1,000 metres as SEIKO has remained firmly at the vanguard of diver's watches world-wide. Nowadays, SEIKO also markets the Pipin series and various other divers' watches to this series, but the starting point for these watches remains the 600-metre model. The creation of this type of professional watch allows SEIKO to support the endeavours of explorers world-wide and help create history. SEIKO will continue to work towards stretching limits with its coming generations of products.


ISO Requirements for Diver's Watches

Visibility : The time, set -time on the rotating bezel, and indication that the watch is running should be visible at 25cm in the dark.

Antimagnetic Properties : Resistance to direct magnetic field of 4800A/m.

Shock Resistance :  Must suffer no damage when dropped   onto a hard surface from a height of over 1metre.

Resistance to an external force :  Resistance  to an outside force of 200 N, testing the resistance of accessories such as the band.

Salt Water Resistance : No change in the casing or accessories and no effect on function after 24 hours in a 3% sodium chloride solution at 23 degrees C.

Resistance to thermal shock : The ability to withstand severe and sudden changes in water temperature , from 40 C to 5 C to 40 C.

Water-tightness at a water overpressure : After being placed for two hours at an overpressure of 1.25  times the depth, they will be placed for one hour at a pressure of 0.3 bar.

Time-preselecteing device :  The ability to measure time using a ring bezel or digital display.

Under-water operation :  Checking that the mechanisms function correctly when immersed in 30 cm of water.

Reliability under water :  No malfunction from being left for 50 hours in 30 cm of water.

Air-tightness in mixed gas :  No malfunction when leaving the watch for 15 days in mixed gas 1.25 times the pressure of the shown depth, followed by a return to normal pressure in under  three minutes.