Not all images were able to load for printing. Please close the print window and try again. Seiko Prospex Revamps the Marinemaster, with the 1968 Heritage Diver HBF001 and JAMSTEC Limited HBF002
The ultimate expression of a classic Seiko diver’s watch.
Prospex Marinemaster… When you hear these two words, you know things are about to become serious. The name Prospex is all about tool watches for Seiko, being the contraction of Professional Specifications. This is the line of watches where you’ll find instruments made for exploration and diving. Marinemaster is another name with great importance for the Japanese brand, first appearing in 2000 with the reference SBDX001, a large, modern and very capable pro-oriented dive watch that represented Seiko’s best. After some time off the grid, the name Marinemaster resurfaced in 2023 with a collection of fairly compact watches, before returning to pure pro-diving style in 2024 with the high-end SLA077 and SLA079. Relying on the same 1968-inspired design, Seiko now introduces a new generation of Prospex Marinemaster, said to be the ultimate expression of a classic diver, and offering multiple upgrades over the previous generation.
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, the Hi-Beat 300m Diver 6159-7001, which was later recreated with the SLA025 and modernised with multiple technical elements borrowed from another important watch, the 1975 Tuna Can. This bold, highly capable and innovative watch has been the source of inspiration for the return of the 300m Marinemaster in 2024, as well as an impressive model released last year, the 600m Marinemaster Professional Titanium SLA081.
As an evolution of the aforementioned 300m models, Seiko updates the collection this year, revising the design ever so slightly, but upgrading most aspects that count: design and materials, movement, comfort and resistance. And the brand does so with two different models, sharing the same technical base, but done in very different visual styles. One is as classic as a diver can be (HBF001), the other pays tribute to a long-standing connection between Seiko and the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), with bold colours and textures (HBF002).
The case of both new Prospex Marinemaster 1968 Heritage Diver is shared, and retains the overall design introduced in 2024 with the previous generation of 300m Marinemaster. It means a robust case inspired by the 1968 Hi-Beat 300m Diver 6159-7001 measuring 42.6mm in diameter and 49.3mm in length. Due to a new and more powerful movement inside, thickness has not been reduced. On the contrary. It is now given for just over 14mm, an increase of 0.7mm (mostly on the caseback). The case retains the classic combination of brushed surfaces and strong lateral polished bevels, as well as deep notches on the bezel and crown. Everything screws down, of course, to guarantee a 300m water-resistance, and the dial is covered by a dual-curved sapphire crystal with anti-reflective coating.
Protection against elements and potential scratches has been at the centre of attention. The case of the Marinemaster HBF001 and HBF002 is made of stainless steel and, like the previous generation, is entirely covered in super-hard coating (the bracelet too). Something new for this generation is the adoption of a ceramic bezel insert, in polished black or blue, depending on the chosen edition. For the rest, the overall silhouette is familiar with its crown at 4 o’clock.
As said, we have two very different expressions of the same technical base here. First is the more-than-classic-but-always-efficient black edition (HBF001). The permanent member of the collection, this version pairs its polished black bezel with a new fine-grain texture to minimise light reflection. The markers (embossed on the dial) and the hands are large and generously coated with LumiBrite, while the date has been relocated to a more natural position at 3 o’clock, with a small luminous marker on its right.
The second edition, the Limited Edition HBF002, is far from being a classic. Made in collaboration with JAMSTEC, it pays tribute to a partnership that began in the 1980s, when two professional Seiko dive 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, will be completed this year. And it is the source of inspiration for this edition.
In addition to having a blue ceramic bezel, this Marinemaster HBF002 comes equipped with a bold textured dial, recreating the trail forged by an icebreaker as it advances through sea ice. In addition to the strong stamped texture is an unusual gradient effect, rendered vertically, ranging from ice white to deep sea blue, and finished with a thick, clear, polished coating. On this edition, the second hand is gold-coloured and the inner flange for the minutes is white. Also, the date window sits in a metallic frame.
Inside the case of these two Marinemaster is a new movement for the collection, the automatic Calibre 8L45 (also used in the Prospex Marinemaster Professional Titanium SLA081 and the KS Vanac collection). Based on a Grand Seiko architecture, the Calibre 9S65, it is a rather tall movement that benefits from a much longer power reserve than its predecessor, the 8L35, as now rated for 72 hours. Accuracy has been improved to now +10 to -5 seconds per day, as well as shock resistance. It is rather pleasantly finished with broad stripes on the plates, bridges and rotor.
Last but not least, the bracelet is a familiar 3-link design but now paired with a new folding clasp, which integrates a micro-adjustment sliding mechanism. It allows adjustments of up to 16mm in 2mm increments by sliding the button inside.
Availability & Price
Released as part of the permanent collection (black HBF001) or as a limited edition of 1,000 pieces (JAMSTEC blue HBF002), these new Seiko Prospex Marinemaster 1968 Heritage Divers are top-of-the-range models, only surpassed by the Marinemaster Professional Titanium SLA081. As such, these do not come cheap, being priced at EUR 3,800 for the standard black edition or EUR 4,100 for the limited edition. For more details, please visit seikowatches.com.
