All Seiko lines › King Seiko › KSK
“KSK”
King Seiko KSK, 38.3 mm (6R55)
Seiko's own name. Where the name comes from
3 versions of this watch are on Seiko's own sites right now, across 2 regions. Last checked Nov 13, 2026.
No Seiko page for this line prints a sub-series. It is filed under KSK because that is the sub-collection Seiko's Hungarian distributor site lists these versions under.
Estimated US price: About $2,515 to $2,605, converted from Seiko's list prices in EUR, HUF.
Retailers ask: $2,540 across 2 listings at 1 seller, checked Nov 13, 2026. See the sellers
Photos are Seiko's own, shown from Seiko's sites. Click a photo to jump to that version.
- Calibre
- 6R55
- Case diameter
- 38.3 mm
- Thickness
- 11.7 mm
- Lug to lug
- 46 mm
- Variants listed now
- 3
- Regions
- 2
Listed means the watch was on an official Seiko regional site or store at the last check. It does not mean it is in stock, and it does not tell us whether Seiko is still making it.
Versions listed now
Same case and movement in every row. What changes is the colour, the strap or bracelet, the finish and where Seiko sells it. Seiko's spec sheets don't state dial colour, so a colour appears only where Seiko's US store tags one.
| Photo | Reference | Colour | Strap / bracelet | Case | Edition | Listed in | Seiko list price | Buy | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| SPB387J1 | Not published | Nemesacél óraszíj Seiko's regional wording | Nemesacél óratok Seiko's regional wording | Regular | 2 regions Hungary, Ireland | 2,295 EUR Ireland · Nov 13, 2026 about $2,515 in US dollars | From 2,295.00 EUR Seiko Boutique Ireland · 1 seller checked | ||||||||||
Where Seiko lists it (2 sites) and its list pricesBuying options (1)Offers seen available at the last check come first, then by item price. Shipping, taxes and import charges are not included. Commission never affects the order.
| ||||||||||||||||||
| SPB391J1 | Not published | Nemesacél óraszíj Seiko's regional wording | Nemesacél óratok Seiko's regional wording | Regular | 2 regions Hungary, Ireland | 2,295 EUR Ireland · Nov 13, 2026 about $2,575 in US dollars | From 2,295.00 EUR Seiko Boutique Ireland · 1 seller checked | ||||||||||
Where Seiko lists it (2 sites) and its list pricesBuying options (1)Offers seen available at the last check come first, then by item price. Shipping, taxes and import charges are not included. Commission never affects the order.
| ||||||||||||||||||
| SPB389J1 | Not published | Nemesacél óraszíj Seiko's regional wording | Nemesacél óratok Seiko's regional wording | Regular | 1 region Hungary | 860,000 HUF Hungary · Nov 13, 2026 about $2,605 in US dollars | No seller matched yet | ||||||||||
Where Seiko lists it (1 site) and its list prices
Buying options (0)No seller offer has been matched to this exact variant yet. | ||||||||||||||||||
Where to buy
Asking prices for new watches at the last check. Each was in stock at that check, but stock moves, and shipping, tax and import charges are not included. Each reference links to the seller's page.
| Seller | Version | Asking price | Checked |
|---|---|---|---|
| Seiko Boutique Ireland | SPB387J1 | 2,295.00 EUR about $2,540 | Nov 13, 2026 |
| Seiko Boutique Ireland | SPB391J1 | 2,295.00 EUR about $2,540 | Nov 13, 2026 |
Estimated US prices use Seiko's US list price where there is one. Otherwise they are the middle of Seiko's list prices in other countries, converted at rates dated Nov 12, 2026 from ExchangeRate-API (free open endpoint). Those list prices include each country's sales tax, so a converted figure usually runs higher than a US price would. Retailer prices are asking prices on the date shown, not sold prices, and leave out shipping, tax and import charges.
The build
| Movement | Mechanikus automata kézi felhúzós | Seiko product page |
|---|---|---|
| Power reserve / battery | 3 nap | Seiko product page |
| Water resistance | 10 bar | Seiko product page |
| Crystal | Domború zafír üveg, tükröződésmentes bevonattal | Seiko product page |
| Seiko case codes | Not published | Seiko catalog data |
Why these share a page
Every version here is published by Seiko with calibre 6R55 and either the same Seiko case code or the same case size. 3 reference codes lead to this page.
What people call it
A name is shown only where a source ties it to a reference on this page. Collector nicknames are not Seiko's names unless the row says so.
| “KSK” | Seiko's own name. Source names SPB387, SPB389, SPB391. “Launched in 1965, the KSK established King Seiko's originality through its design.” | Seiko Watch Corporation read 2026-11-12 |
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