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King Seiko KSK, 37 mm (6R31)
5 versions of this watch are on Seiko's own sites right now, across 6 regions. Last checked Nov 13, 2026.
Estimated US price: About $1,685 to $2,215, converted from Seiko's list prices in EUR, HUF, PHP and more.
Retailers ask: no retailer listing matched yet.
Photos are Seiko's own, shown from Seiko's sites. Click a photo to jump to that version.
- Calibre
- 6R31
- Case diameter
- 37 mm
- Thickness
- 12.1 mm
- Lug to lug
- 43.6 mm
- Variants listed now
- 5
- Regions
- 6
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 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 | SPB283 Also coded SPB283J1 | Not published | Not stated 129 g | Stainless steel Translated from Seiko's regional page | Regular | 4 regions France, Malaysia, Singapore, Türkiye | 1,800 EUR France · Nov 13, 2026 about $2,040 in US dollars | No seller matched yet | ||||||||
Where Seiko lists it (4 sites) and its list pricesBuying options (0)No seller offer has been matched to this exact variant yet. | ||||||||||||||||
 | SPB279 Also coded SPB279J1 | Not published | Not stated 129 g | Stainless steel Translated from Seiko's regional page | Regular | 3 regions France, Hungary, Türkiye | 1,800 EUR France · Nov 13, 2026 about $2,215 in US dollars | No seller matched yet | ||||||||
Where Seiko lists it (3 sites) and its list pricesBuying options (0)No seller offer has been matched to this exact variant yet. | ||||||||||||||||
| SPB287J1 | Not published | Nemesacél óraszíj Seiko's regional wording | Nemesacél óratok Seiko's regional wording | Regular | 1 region Hungary | 680,000 HUF Hungary · Nov 13, 2026 about $2,060 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. | ||||||||||||||||
 | SPB291 Also coded SPB291J1 | Not published | Not stated 129 g | Stainless steel Translated from Seiko's regional page | Seiko Boutique Special Edition | 1 region France | 2,000 EUR France · Nov 13, 2026 about $2,215 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. | ||||||||||||||||
 | SPB365 Also coded SPB365J1 | Not published | Not stated Clasp: Deployment clasp with push button release 129 g | Stainless steel | Seiko Watchmaking 110th Anniversary Limited Edition | 1 region Philippines | 107,470 PHP Philippines · Nov 13, 2026 about $1,685 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
No retailer listing has been matched to a version on this line yet.
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 | Automatic with manual winding | Seiko product page |
|---|---|---|
| Functions | Stop second hand function | Seiko product page |
| Power reserve / battery | Approx. 70 hours | Seiko product page |
| Water resistance | 10 bar | Seiko product page |
| Crystal | Box shaped sapphire crystal | Seiko product page |
| Lug width | 19 mm | Seiko product page |
| Seiko case codes | 6R31-00D0, 6R31-00G0 | Seiko catalog data |
Why these share a page
Every version here is published by Seiko with calibre 6R31 and either the same Seiko case code or the same case size. 9 reference codes lead to this page.
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