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Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Seiko’s King Seiko KSK 6R 3 Days 36mm collection consists of three date-free automatic watches: the blue SPB457, green SPB459 and burgundy SPB461. Each measures 36.1 mm across and uses Seiko’s 6R51 movement. They are the smaller, simpler-dial alternative to the 38.3 mm King Seiko models that use the 6R55 and display a date.
Which references and dial colors are available?
Seiko’s KSK collection lists three 36.1 mm references, distinguished by dial color:
| Reference | Dial color | Movement | Date |
|---|---|---|---|
| SPB457 | Blue | 6R51 | No |
| SPB459 | Green | 6R51 | No |
| SPB461 | Burgundy | 6R51 | No |
The colors were described in 2024 launch coverage as saxe blue, ivy green and burgundy red. That coverage relayed Seiko’s stated inspirations: an Oxford shirt for the blue dial and Ivy-style references for the green and burgundy dials. Those are design inspirations, not claims about a broader historical connection. Fratello’s launch coverage reported the trio on August 7, 2024; Seiko’s regional KSK collection page lists the references and movement.
How do the 36 mm models compare with the larger King Seiko group?
The closest comparison in the supplied lineup is the 38.3 mm SPB387, SPB389 and SPB391 group. Fratello’s launch coverage describes those models as using caliber 6R55 and including a date; the 36 mm trio is 2.2 mm smaller in listed diameter, uses caliber 6R51 and has no date.
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- KHAKI GREEN DIAL: this rugged sports watch features a khaki green dial patterned to mirror the shape of the bezel’s edge, with Lumibrite dial indicator hands and markers for low light and a magnified day/date calendar
- BLACK BEZEL: this versatile men’s watch features a black ceramic unidirectional bezel with distinctive scalloped edging, for elapsed timing
- AUTOMATIC & MANUAL: SRPE05 automatic watches for men power up with your natural movements, and feature the ability to wind manually, with 41 hours of reserve power
- WATER-RESISTANT: these rugged stainless steel dive watches for men feature a khaki green silicon strap, and are both stylish and robust, following ISO standards for scuba, and are water-resistant to 200 meters
- 4R36 CALIBER: equipped with the reliable 4R36 caliber, these precise men’s wrist watches ensure the most accurate timekeeping
| Models | Diameter | Movement | Dial display |
|---|---|---|---|
| SPB457, SPB459, SPB461 | 36.1 mm | 6R51 | Date-free |
| SPB387, SPB389, SPB391 | 38.3 mm | 6R55 | Date |
The smaller diameter and absence of a date are useful distinctions when choosing between the groups. They do not establish how either watch will fit a particular wrist; the published dimensions are not a substitute for trying one on.
What are the 36 mm trio’s dimensions and specifications?
Seiko Boutique UK’s SPB461 product sheet lists a 36.1 mm case diameter and 11.6 mm thickness. It also gives a 43.0 mm case length, 19.0 mm lug width and 10 bar water resistance. The PDF does not show a publication date, and these are manufacturer specifications rather than independent measurements.
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- STUNNING BLUE DIAL: this automatic men's watch features a deep blue, pressed pattern and gloss finish surrounded by a stainless steel watch case
- AUTOMATIC: these self-winding, automatic men's watches are powered by your movement, with a power reserve of 41 hours
- STAINLESS STEEL: features a durable stainless steel watch case and bracelet with see through caseback
- WATER-RESISTANT: these men's wrist watches are water-resistant down to 50 meters
- 4R35 CALIBER: equipped with the reliable caliber 4R35 automatic movement, this accurate men's watch keeps precise time
- Case diameter: 36.1 mm
- Thickness: 11.6 mm
- Case length: 43.0 mm
- Lug width: 19.0 mm
- Water resistance: 10 bar
- Crystal: boxed-shaped sapphire with anti-reflective coating on its inner surface
The listed 19 mm lug width gives a starting point for considering an interchangeable strap, but check the exact strap and fit before buying. The specification sheet describes the SPB461; confirm details for the other references with the relevant regional product listing.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What does the 6R51 movement offer?
The 6R51 is an automatic movement. Seiko’s SPB461 product specification lists a 72-hour power reserve; Seiko describes the wider 6R family as offering approximately three days and its collection text gives approximately 70 hours. For a precise figure, the SPB461 sheet’s listed specification is 72 hours. Seiko Boutique UK’s SPB461 specification sheet provides the exact product figures.
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- Rotatable Compass Ring
- Secure Crown
- Transparent & Secure Case Back
How does the design connect to King Seiko’s history?
The KSK design traces its lineage to King Seiko watches launched in 1965. Seiko emphasizes the broad, patterned marker at 12 o’clock and the sharp case design as defining elements. On the current models, the maker describes faceted lugs with mirror and hairline finishes, a boxed-shaped sapphire crystal, and a bracelet with beveled surfaces. These are Seiko’s design descriptions, not independent assessments of finishing or wear.
What did the watches cost at launch, and what is the price now?
Prices vary by market and date. Fratello reported a launch price of €2,000 including VAT in 2024. Seiko Boutique UK’s SPB461 sheet lists an RRP of £1,720 including VAT, but its PDF has no publication date. Neither figure should be treated as a current global price: check the local Seiko or authorized-retailer listing for the price and availability in your region. Seiko’s Spanish boutique category is another regional retail reference, not a worldwide stock indicator.
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Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
