Seiko introduced its first diver’s watch in 1965. In the decades since, the company has developed new technologies, designs, and features that have made its collection of Seiko Prospex diver’s watches a favorite among professionals and enthusiasts the world over. Continuous innovation and enhancements in safety, reliability, and ease of use have made Seiko a leader in the category. The Marinemaster is Seiko’s flagship series for diving, equipped with a robust and high-performance movement with stable accuracy designed exclusively for diver’s watches. It represents the top tier of Prospex watches in a diving category that is integral to the history and culture of Seiko. Originally launched in the Japanese domestic market, the series has been revitalized and makes its global debut with three new Prospex Marinemaster creations – one limited edition and two mainline introductions.

Inspired by Seiko’s first diver’s watch from 1965

Representing the official global launch of the Marinemaster line, each new watch takes its design inspiration from what is known to fans as the iconic 62MAS of 1965, Seiko’s first watch for divers and the first diver’s watch made in Japan.

The 62MAS, Seiko's and Japan's first diver's watch.

A textured horizontal stripe pattern expresses lapping waves on each watch’s dial while adding a stylish touch to the new design, which features “Marinemaster” printed just below the Seiko logo at the 12 o’clock position. A silvery-white dial graces a limited-edition version commemorating the 100th anniversary of the Seiko brand, while light blue and black dials join the Prospex collection as standard watches.

Each watch’s hour, minute, and seconds hands inherit the design of those found on the 1965 diver’s watch, with legibility in dark lighting ensured by Lumibrite-filled indexes and a luminous pip on the unidirectional bezel.

Seiko's slimline mechanical diver's watch
Inside each watch is the automatic Seiko Caliber 6L37, the first movement in the slimline Caliber 6L series developed specifically to meet the rigors of diving while allowing a pleasingly slender profile and a high level of comfort on the wrist. Caliber 6L37 has been adapted from the earlier Caliber 6L35 to have greater shock resistance while maintaining the slender profile that characterizes the 6L movement family.

For the first time in a Seiko diver’s watch, the new Marinemaster creations feature an exhibition case back, allowing a view of this finely finished, high-performance mechanical movement. The development of a diver’s watch with a see-through case back, a feature that tends to add thickness, presented its own challenges. The new watch needed to maintain the high level of water and shock resistance that Prospex usually achieves with a closed case back while also keeping the profile thin. By reconsidering the case structure and using the slimline Caliber 6L37, Seiko created what is its thinnest mechanical diver’s watch currently (12.3mm) while adding a view of the movement.

The new 39.5mm case design balances functionality and aesthetics thanks to dramatic chamfering on the bezel and the case, which creates a sleeker and more modernized appearance while retaining the essential profile of the classic 62MAS from 1965. The combination of the hairline and mirror finishes on the case and bracelet endows the design with a sophisticated contrast and elegance.

A New Bracelet
Wearability and comfort are paramount in Seiko Prospex diver’s watches, and these qualities have been carefully cultivated in the new Marinemaster thanks to an entirely new bracelet that features ellipse-shaped links with mirror-finished, dual-curved surfaces. This, in combination with the slender case and high-performance movement, ensures that the new Marinemaster is imbued with the essence of a Seiko classic while also looking ahead to the future.

The new Marinemaster creation with a dial in silvery-white will be offered as a limited edition of 1,000. All three watches will initially be exclusive to Seiko Boutiques, starting in December, and then will be available at select retail partners worldwide in January 2024.

One hundred years of Seiko on the dial
Since the beginning of Seiko in 1881, the company has continued to innovate in line with the founder's philosophy to be "Always one step ahead of the rest." In 1924, the company introduced the first wristwatch with “Seiko” on the dial, signifying the beginning of the Seiko brand. The year 2024 marks the 100th anniversary of this landmark event.

Seiko Prospex Marinemaster 1965 Diver’s Modern Re-interpretation: SJE099, SJE101

                SJE099

                SJE101