Two new releases for the 1968 Heritage Diver’s GMT introduce fresh dial treatments and spec upgrades. For collectors who know Seiko’s Diver lineage, it is a meaningful update to a classic reference.

Seiko’s dive watch story is – excuse the pun – worth diving into. The brand produced Japan’s first diver’s watch in 1965 – the 62MAS – an automatic model that was field-tested to 150 meters during the 8th Japanese Antarctic Research Expedition. Its seriously deep credentials were established somewhere considerably more demanding than a swim or civilian-style scuba jaunt. By 1968, Seiko had introduced Japan’s first high-beat automatic movement and incorporated it into what would become one of the marque’s most iconic case.

That 1968 case profile is the DNA running through the current Heritage Diver’s GMT family. Seiko previously reintroduced a modern re-interpretation in 2023, pairing it with the then-new Caliber 6R54 and a GMT complication. At the time, the watch achieved a water resistance of 200 meters and an impressive 72-hour power reserve. The evolution of the Diver continues this story of careful consolidation and improvement.

The biggest upgrade to the newest creations is water resistance, now rated to an impressive 300 meters. While of course it remains unlikely that most owners will ever put this to the test in real conditions, the fact is that this kind of technical achievement matters for an audience who values genuinely serious watchmaking performance. 300 meters asserts genuine dive credentials, bringing this model into professional territory in line with the Seiko Diver’s 60th Anniversary Limited Edition, SPB509, released in 2025.

The case stays faithful to the 1968 original at 42mm in diameter and 13.3mm thick, with mirror-finished case sides. The bezel — unidirectional, as dive protocols demands – features a ceramic insert, while a screw-down crown and screw caseback complete the water-resistance architecture, and a sapphire crystal with inner anti-reflective coating bestows that all-important legibility for divers.

Luminous coating has been applied to the hands, indices, and 12 o’clock bezel marker- another crucial detail for a diver- and this material is Seiko’s in house LumiBrite that delivers the non-negotiable visibility at depth. The crown is positioned at 4 o’clock, the same placement as the original and constructed this way so that it keeps it better aligned with the wrist during wear; a neat ergonomic detail that will be appreciated by the wearer.

Power comes from the Caliber 6R54, an automatic GMT movement. It is an automatic with manual winding capability, a 72-hour power reserve, 24 jewels, and an accuracy rating of +25 to -15 seconds per day. The GMT function displays a second time zone via a 24-hour hand read against a fixed inner scale.

Alongside the water resistance upgrade, Seiko has introduced a new redesigned and improved three-fold clasp with secure lock and push-button release incorporating a slide adjuster that moves in six steps of approximately 2.5mm each, a total adjustment range of around 15mm. The intent is practical: wrist circumference changes between warmer air and cold water, morning and evening and diving and everyday activities. So, a clasp that accommodates this without requiring a watchmaker or a tool is genuinely useful – especially for a watch that is designed to be worn, used and enjoyed in places presumably somewhat far from the local watch servicing center. The stainless-steel bracelet is standard across both references and includes a super-hard coating for added scratch resistance.

The two new references – HBC001 and HBC002 – also Introduce fresh dial treatments to the Heritage GMT family. Both are offered at USD 1,700.

The 1968 Heritage Diver’s GMT was already a well-resolved watch, and the updates – a jump to 300 meters water resistance and the improved clasp system, can genuinely be considered a meaningful update to a much-loved model. For Seiko collectors who want something with real dive credentials and horological context, these new releases are certainly worth making a plunge for.

Tech Specs: Seiko Prospex Heritage Diver’s GMT

References HBC001, HBC002
Movement Caliber 6R54; automatic with manual winding; 72-hour power reserve; 24 jewels
Functions Hours, minutes, seconds, date; GMT/dual-time display; stop-seconds
Case 42mm diameter; 13.3mm thickness; 48.6mm lug-to-lug; stainless steel; ceramic bezel insert; sapphire crystal with inner AR coating; 300m water resistance; magnetic resistance 4,800 A/m
Bracelet Stainless steel; three-fold clasp with secure lock, push-button release, and slide adjuster (15mm range in 6 × 2.5mm increments)
Price USD 1,700