55 years ago, Seiko introduced its, and Japan's, first ever diver's watch. With an automatic movement and water resistance to 150m, it proved its reliability when it was used by members of the Japanese Antarctic Research Expedition from 1966 to 1969. In the years that followed, Seiko created many other diver's watches that found favor with professional divers and adventurers alike, thanks to their high quality and reliability.
Three of the most important landmarks from Seiko's first decade as a maker of diver's watches are now re-created in celebration of the 55th anniversary of that first achievement. They are offered in the Prospex collection which is today synonymous with excellence in watches for use in all types of sports and challenging environments.
1965 - 1975Diver's Re-creation
While faithful to the original designs, all three watches are fully up to date in their specifications and execution. The greatest advance is in the grade of stainless steel used in the construction of the three watches. To be known as Seiko's "Ever-Brilliant Steel," thanks to the brilliant white hue that gives this trilogy of watches its unique look, this grade of steel is more corrosion resistant than that which is used in most high-end watches today.* It is used for the first time** in the watch industry for the cases of the 1965 and 1968 re-creations and the bezel of the 1975 re-creation whose case is, like the original, in titanium. This material is used extensively in the surfaces, linings, bolts and other components of marine structures and vessels so as to avoid corrosion in a chloride-rich environment such as sea water. It presents many challenges in the manufacture of watch cases but, thanks to the experience and innovative techniques of the Seiko team, these challenges were overcome and Ever-Brilliant Steel is now set to bring a new level of durability to the diver's watch.
The 1965 and 1968 re-creations are powered by the high beat 8L55 movement and the 1975 re-creation carries Caliber 8L35, both developed and assembled expressly for diver's watches at the Shizukuishi Watch Studio. All three have sapphire crystals, and the 1975 re-creation has an increased anti-magnetic resistance of 40,000 a/m thanks to the dial made of pure iron. The 1975 re-creation has an increased anti-magnetic resistance of 40,000 a/m thanks to the dial made of pure iron.
* This stainless steel has a PREN (Pitting Resistance Equivalent Number) value 1.7 times higher than that of the grade of steel used in most high-end watches. PREN is a widely accepted standard used to measure corrosion resistance.
** as of December 2019, based on Seiko's research.