Encyclopedia / Seiko / Prospex Alpinist
No real new deal right now · checked Oct 19, 2026, 10:06 PM ET
$700 – $1,200 pre-owned street range
SPB121 (discontinued) (median ~$800)
No new SPB121 found at Jomashop or WatchMaxx. Thin market: only 19 Chrono24 listings on the first page. Seiko US now lists the SPB507 at $900, and the SPB503 and SPB505 at $995.
What it really costs
| Market | Price | Source |
|---|---|---|
| Seiko US retail | SPB121 discontinued · SPB507 $900 | seikowatches.com |
| Grey-market new | No SPB121 found | — |
| Pre-owned SPB121 | about $700 – $1,200 (median ~$800; 19 listings) | Chrono24 |
All prices in USD, checked Oct 19, 2026 (ET). Pre-owned ranges are the middle 80% of asking prices on the first Chrono24 results page for that ref (about 60 listings, used and some unworn), fixed-price listings only. Grey-market = brand-new from a non-authorized dealer.
Buying guide
Key references
| Ref. | What it is | US retail |
|---|---|---|
| SPB121 | 39.5 mm, green dial, internal compass bezel, 6R35 (discontinued) | Discontinued |
| SPB507 | Current Alpinist, 39.5 mm, 6R55, 72 h | $900 |
Which one I'd pick
Pre-owned SPB121 vs new SPB507: a clean SPB121 around the $800 median costs about the same as a new SPB507 at $900. The SPB507 has the newer 72-hour movement and a full warranty; the SPB121 is the version most people mean by 'the Alpinist'.
What to check before you buy
- Box and papers: with a discontinued model, a full set helps resale.
- Ref check: Alpinist listings mix many refs and dial colours. Match the ref before comparing prices.
- Condition: check the internal compass bezel turns cleanly with its crown.
Alternatives worth a look
- Seiko Prospex 'Turtle': Seiko's cult diver for about half the price. (45 mm stainless steel, Calibre 4R36, retail $525 (SRPE93))
- Hamilton Khaki Field Mechanical: A hand-wound field watch, below retail. (38 mm stainless steel, Calibre H-50, retail $675 (38 mm))
- Rolex Explorer (36 mm): The explorer's watch, if budget isn't a concern. (36 mm Oystersteel, Calibre 3230, retail $7,900 (124270))
History
Seiko launched the Laurel Alpinist in 1959, as mountaineering and skiing took off in Japan. Seiko calls it its first sports watch.
The SPB121 was a modern Prospex take on the idea: a 39.5 mm case with a green dial and an internal rotating compass bezel. Seiko no longer lists it on its US site.
Seiko's current US Alpinist line lists the SPB503, SPB505 and SPB507. The SPB507 uses the 6R55 automatic with about 72 hours of power reserve and a sapphire crystal with a date magnifier.
Specifications
| Brand | Seiko |
|---|---|
| Model | Prospex Alpinist |
| Key references | SPB121 (discontinued), SPB507 (current) |
| Launch year | 1959 (Alpinist) |
| Case | 39.5 mm stainless steel |
| SPB507 thickness | 12.7 mm |
| SPB507 lug-to-lug | 46.4 mm |
| SPB507 crystal | Sapphire with magnifier |
| SPB507 water resistance | 20 bar |
| SPB507 weight | 88 g |
| Movement | Calibre 6R35, automatic (SPB121); 6R55 (SPB507) |
| Power reserve | About 70 hours (SPB121); about 72 hours (SPB507) |
| Water resistance | 200 m |
| Approx. US retail (Oct 2026) | $900 (current SPB507, Seiko US) |
Specs from the brand's official product page for the main reference. Retail prices are list prices, not market value, and change often.
Highlights
- Internal rotating compass bezel
- Cathedral hands
- Sapphire crystal
FAQ
Is the Seiko Alpinist SPB121 discontinued?
Seiko's US site no longer lists it. Its current Alpinist models are the SPB503, SPB505 and SPB507 (checked Oct 19, 2026).
How much is a used SPB121?
On Chrono24, the middle of the market was asking about $700 to $1,200, with a median of about $800 (19 listings).
How much is the new Seiko Alpinist?
Seiko US lists the SPB507 at $900 and the SPB503 and SPB505 at $995.
When did Seiko make the first Alpinist?
In 1959, the Laurel Alpinist.
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