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Seiko Diver's 1968 300M Heritage GMT 42mm Mens Watch Pacific Green
Ref. HBC001J1
Sits in Seiko’s upper tier here — more premium than three quarters of the Seiko watches we list, which start at £110.
Price range £110 to £3,550 across 192 Seiko watches in stock.A reinterpretation of Seiko's 1968 diver's watch, the HBC001J1 wears its 42mm stainless steel case with a super-hard coating across a 13.3mm profile, sitting 48.6mm lug to lug. The unidirectional rotating bezel carries a green ceramic insert, complementing the rich Pacific Green dial beneath an anti-reflective sapphire crystal. LumiBrite covers the hands, indices, and bezel markings throughout. The in-house calibre 6R54 is an automatic movement with manual winding, a 72-hour power reserve, and a dedicated 24-hour GMT hand for tracking a second time zone. The three-link bracelet closes with a three-fold clasp featuring a toolless slide adjuster across six increments. Water resistance is rated to 300 metres.
- Reference
- HBC001J1
- Brand
- Seiko
- Case size
- 42mm
- Case thickness
- 13.3mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Green
- Crystal
- Sapphire
- Bezel
- Unidirectional rotating
- Movement
- Automatic
- Calibre
- 6R54
- Functions
- GMT, Date
- Water resistance
- 300m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Clasp
- Three-fold clasp
- Lume
- LumiBrite
- Retailer
- Goldsmiths
Additional specifications
- Lug-to-lug
- 48.6mm
- Power reserve
- 72 hours
Learn more about Seiko
Kintaro Hattori opened a watch and clock shop in Tokyo in 1881, aged twenty-one, and began manufacturing under the name Seikosha — roughly, house of exquisite workmanship — in 1892. The Seiko name appeared on watches from 1924.
The company's significance is that it broke the Swiss monopoly twice. First on precision: Seiko was appointed official timekeeper of the 1964 Tokyo Olympics and built the quartz chronometers and printing timers to do it, and in the 1960s its movements placed highly at the Neuchâtel and Geneva observatory trials against the best Swiss houses.
Then on technology. On Christmas Day 1969 Seiko released the Astron, the world's first quartz wristwatch, accurate to five seconds a month where mechanical watches managed that per day. The consequences for Switzerland were catastrophic — employment in the Swiss industry fell by roughly two-thirds over the following decade. Seiko deliberately did not enforce its quartz patents, allowing the technology to spread.
The same year it produced the 6139, among the first automatic chronographs, and it has since introduced Kinetic, Spring Drive — a hybrid regulating a mechanical mainspring electronically, giving a perfectly gliding seconds hand — and its own dive and field lines.
Seiko remains fully vertically integrated, making its own hairsprings, quartz crystals, and even the Zaratsu-polished cases, at price points from under a hundred pounds upward.
- 1881
- Kintaro Hattori opens his Tokyo shop.
- 1924
- The first watches carry the Seiko name.
- 1964
- Official timekeeper of the Tokyo Olympics.
- 1969
- The Astron becomes the first quartz wristwatch.
- 1999
- Spring Drive enters production.
Also in 6 collections
This watch appears in Stainless Steel Watches (3,157), Automatic Watches (1,753), Sports Watches (793), Dive Watches (566), Green Dial Watches (436) and GMT Watches (252).
Best of 2 retailers
What the specifications mean
A mechanical watch built to be worn hard and got wet.
Strengths
- 300m water resistance, rated for actual diving
- 48.6mm lug-to-lug keeps the 42mm case wearable
- Sapphire crystal, which resists scratching
- 72-hour reserve survives a weekend off the wrist
- Luminous hands and markers for low light
Price history
This watch is currently at its highest recorded price. It was £1,600 on 10 August. Prices are checked every day, and we record any changes.
Seiko Diver's 1968 300M Heritage alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | HBC001J1 | R32105313 | L37693967 |
|---|---|---|---|
| Price | £1,700 | £1,760 | £1,550 |
| Case size | 42mm | 42mm | 42mm |
| Water resistance | 300m | 300m | 300m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Stainless steel bracelet | Stainless steel bracelet | Stainless steel bracelet |
| Power reserve | 72 hours | 80 hours | — |
| This watch | Closely matched | Closely matched |
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 300m it is rated for swimming, snorkelling and recreational diving.
Water resistance explainedWill the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Sapphire, mineral and acrylic comparedDoes it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
Quartz, automatic and solar comparedHow long does it run for when it's not worn?
About 72 hours fully wound — enough to sit off the wrist over a weekend and still be running.
Will it fit my wrist?
Lug-to-lug is 48.6mm, which suits wrists from roughly 16.5cm (6½ inches) upward.
Lug-to-lug decides fit more than case diameter does.
How to size a watch to your wristIs it a men's or women's watch?
Listed as men's.
Cheapest place to buy
Both Mappin & Webb and Goldsmiths list it at £1,700, so choose on delivery and warranty rather than price.
Has the price changed recently?
It's currently at its highest recorded price. It's ranged between £1,600 and £1,700, today it's £1,700.
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