Vintage Seiko Divers: A Collector's Guide from 62MAS to Tuna
In 1965 Seiko released Japan's first diver's watch, a 150-metre automatic now known to collectors as the 62MAS. Within a decade the company had built a 300-metre high-beat diver, the cushion-cased 6105 and a 600-metre professional watch with a titanium case and a protective outer shroud. These are the references that made Seiko's name among divers, and today they are among the most sought-after vintage Japanese watches anywhere.
The references that matter
| Reference | Introduced | What it is |
|---|---|---|
| 6217-8000 / 8001 (62MAS) | 1965 | Japan's first diver's watch: 150 m, automatic, a slim case with a rotating bezel. The founding piece of every serious Seiko collection. |
| 6215-7000 | 1967 | A 300 m professional diver with a one-piece case and a hi-beat movement, rare and highly prized. |
| 6105-8000 / 8009 | 1968 | The first 6105: a 150 m automatic with a crown at four o'clock, in a cushion-shaped case. |
| 6159-7001 | 1968 | A 300 m hi-beat diver at 36,000 beats per hour, built for professional use. |
| 6105-8110 / 8119 | 1970 | The second 6105, with a broader cushion case and protected crown. The Japanese adventurer Naomi Uemura wore one on his expeditions, and in Japan it carries his name; abroad it is famous from the film Apocalypse Now. |
| 6159-7010 | 1975 | The 600 m Professional Diver with a titanium case under a protective shroud, the first of the watches collectors call the Tuna. |
Later references such as the 6309 and 7002 automatics of the 1970s and 1980s, and the SKX007 of 1996, carried the same design language to a much wider public and remain good entry points.
Dating a Seiko by its serial number
Seiko serial numbers on the caseback encode the date of manufacture. The first digit is the last digit of the year, and the second digit is the month, with 1 to 9 for January to September and O, N and D for the last three months. A 6105-8110 with a serial beginning 74 was made in April 1974 or 1984; because the reference was produced in the 1970s, the decade is clear. The serial should agree with the movement and the dial style of that period.
What to check before buying
- Dial and hands: original dials with even, aged lume are worth far more than redials or replacement hands. Look closely at the printing and the lume plots.
- Bezel insert: aftermarket inserts are common. Check the font, the colour and how the triangle at twelve is filled.
- Case: cushion cases should keep their sharp transitions between brushed and polished surfaces. Heavy polishing softens them and lowers value.
- Crystal and crown: the correct crystal shape and signed crown matter to collectors, as does a crown that screws down smoothly.
- Movement: the calibre should match the reference (6105A or 6105B for the 6105, 6159A for the hi-beat and Tuna). A service record helps.
- Water resistance: treat any vintage diver as splash resistant until it has been pressure tested after service.
Why so many good examples are in Japan
These watches were sold in large numbers at home, and Japanese owners and specialist workshops have kept many of them running through decades of servicing. Original dials, correct bezels and service histories appear more often in Japan than elsewhere, which is why collectors abroad watch the Japanese market closely.
How each watch reaches you
Every watch in our Japanese Horology room is examined in Japan before it ships, with the dial, bezel, case and movement photographed, and travels insured and tracked. Each carries our authenticity guarantee: should an independent written opinion find a piece not genuine within 30 days, we refund the price and the cost of its return.
Questions collectors ask
Is a vintage Seiko diver still water resistant?
Only after new gaskets and a pressure test. Many owners wear them as everyday watches and keep them away from swimming unless freshly tested.
Should I buy a serviced watch or one untouched?
A recent service with original parts retained is ideal. Unserviced watches can hide worn parts, but a heavily restored watch with replaced dial or hands is worth less to collectors.
Can you find a specific reference, such as a 62MAS or a 6215?
Yes. Our Hunting Salon™ searches for specific references and checks them before purchase, and the curator desk replies within one to three business days.
Continue reading
- Grand Seiko and Credor: a collector's guide.
- The Rise of Japanese Independent Horology.
- Japanese Condition Ranks Explained.