Description
Seiko has added two earth-toned dials to the 5 Sports Field GMT: HDB001 in olive green and HDB002 in khaki beige. Nothing mechanical has changed — the 4R34 automatic and the fixed 24-hour bezel carry over from the black-dialled SSK023 and SSK025 that launched the series in 2024 — but at €470 these remain among the cheapest mechanical GMT watches you can buy from a brand that makes its own movements.
The proposition has not needed changing. A fixed 24-hour bezel, a red-orange fourth hand, a 39.4mm steel case and a five-link bracelet add up to something that reads as a small Explorer II at roughly a twentieth of the price. The new colours simply move the series away from the utilitarian black and toward something closer to a field watch's natural register.
Design
The case is 39.4mm wide, 13.6mm thick and 47.9mm lug to lug in brushed and polished stainless steel, with a push-pull crown and a screwed display caseback. The bezel is fixed rather than rotating, radially brushed and engraved with a 24-hour scale filled in black or grey depending on the reference. The crystal is curved Hardlex — Seiko's hardened mineral glass, not sapphire, which is the clearest place the price shows.
Both dials are matte and lightly textured. HDB001 is olive green, HDB002 a khaki beige, and on each the raised numerals and applied hour markers are filled with LumiBrite, with a second 13–24 scale printed inside the chapter ring and a framed date window at 3 o'clock. The hands are brushed metal with LumiBrite; the GMT hand is picked out in red-orange — Monochrome describes it as red-toned, Time+Tide as bright orange. The 5-link brushed steel bracelet closes on a folding clasp with a secure lock.
Specifications
- References: HDB001 (olive green dial); HDB002 (khaki beige dial)
- Case diameter: 39.4mm
- Case thickness: 13.6mm
- Lug-to-lug: 47.9mm
- Case material: Stainless steel, brushed and polished
- Bezel: Fixed, radially brushed, engraved 24-hour scale
- Crystal: Curved Hardlex
- Caseback: Screwed, see-through
- Water resistance: 100m
- Dial: Matte textured olive green or khaki beige, raised numerals and LumiBrite-filled markers, 13–24 hour scale, framed date at 3 o'clock
- Movement: Seiko calibre 4R34
- Type: Automatic, 24 jewels
- Complications: Caller GMT — independently adjustable 24-hour hand in one-hour increments; date
- Frequency: 21,600 vph (3 Hz)
- Power reserve: 41 hours
- Bracelet: 5-link brushed stainless steel, folding clasp with secure lock
- Limited edition: No
- Price: €470 / USD 450 / GBP 410
- Availability: Available now
What's Exciting
The 4R34 is the reason this series exists. It is a caller GMT, not a flyer — the 24-hour hand is the one you set independently, so it is built for tracking a second zone from home rather than for resetting local time on landing. Purists prefer the flyer arrangement, but the caller is the more honest fit for how most people actually use a second time zone, and Seiko is one of very few manufacturers putting any in-house mechanical GMT into a case at this price.
What the new colours do is fix the one thing that held the original back. The black-dialled SSK023 and SSK025 looked like what they were: an inexpensive Seiko. Olive and beige, matte and textured, with a brushed fixed bezel above them, give the watch a coherence it did not have before. At €470 you are accepting Hardlex over sapphire, 3 Hz over 4, and 41 hours rather than 70 — all reasonable trades for a mechanical GMT on a decent bracelet, and there is very little else in the category to argue with it.
History
The Seiko 5 name goes back to 1963 and the Sportsmatic 5, built around five guarantees: automatic winding, day-date, water resistance, a recessed crown and a durable case. It became the archetype of the affordable, over-engineered Japanese automatic and stayed in production, in one form or another, ever since.
The GMT chapter is much newer. Seiko put the 4R34 into the 5 Sports line in 2022 with the SSK001 series, the first time a mechanical GMT arrived at this price from a major manufacturer, and the Field GMT followed in 2024 with the black-dialled SSK023 and SSK025 — trading the dive bezel for a fixed 24-hour one and moving the design toward Rolex's Explorer II. HDB001 and HDB002 are the first colour expansion of that Field sub-series.
