Seiko’s journey in diver’s watchmaking began in 1965 with Japan’s first diver’s watch, which accompanied members of the Japanese Antarctic Research Expedition to the South Pole from 1966 to 1969.

This model was followed by the creation of the nation’s first 300m water-resistant diver’s watch in 1968. In the decades since, Seiko has developed new technologies, designs, and features that have made its diver’s watches a trusted favorite among professionals and enthusiasts worldwide.

The company’s legacy of testing the limits of the modern sports watch and supporting marine conservation continues through its partnership with the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), which began in the 1980s. In 1983, two professional diver’s watches rated to 600 meters were successfully tested aboard SHINKAI 2000, a manned research submersible operated by JAMSTEC.

For decades, JAMSTEC has been engaged in marine research to advance science and technology and promote academic progress through various initiatives. One such effort is the Arctic Research Program. As part of this, Japan’s first research vessel with icebreaking capabilities, Mirai II (the word mirai means “future” in Japanese), will be completed this year, enabling data collection in ice-covered seas.

Inspired by the spirit of bold exploration that connects JAMSTEC and Seiko, two new diver’s watches join Prospex’s flagship Marinemaster series. The first is a JAMSTEC collaboration, and the second is a continuous production model. Both are powered by Seiko’s self-winding Caliber 8L45 mechanical movement and represent the pinnacle of the Seiko 300m water-resistant diver’s watch.

Honoring a spirit of exploration and forging new paths

The collaboration model showcases a new textured dial that imagines the trail forged by an icebreaker as it advances through sea ice, symbolizing how Arctic research paves the way for the future.

Its vertically oriented blue gradient, which deepens at the center, is finished with a thick, clear coating and then polished, echoing the boundless, crystalline depth of the Arctic Ocean. The blue ceramic bezel enhances the beauty of the dial while providing exceptional scratch resistance.