King Seiko Hi-Beat 5626-7000 – Caliber 5626A, Suwa Seikosha – gold-plated case with gold medallion – January 1969 – freshly serviced

On the case back sits a round gold medallion with the lettering SEIKO, below it the letters KS and the logo of the Suwa factory.

Not every Seiko received this medallion. It was reserved for top-tier lines and is today one of the first things collectors look for on the back of a King Seiko. On worn examples, it is often rubbed smooth or the embossing has vanished. Here, it is completely intact.

King Seiko – the line from the "other" factory

For decades, Seiko maintained two completely separate production facilities that competed against each other: Suwa Seikosha in Nagano Prefecture and Daini Seikosha in Tokyo. Both developed their own movements, maintained their own model series, and competed for the top position. Management explicitly encouraged this—whichever factory built the better movement received the contract.

In 1960, Suwa introduced the first Grand Seiko. Daini responded in 1961 with the first King Seiko. What followed is one of the most productive rivalries in watchmaking history.

With the 56 series, the dynamic reversed: The caliber 5626 originated from Suwa—the very same factory that built Grand Seiko. Suwa thus supplied both the Grand Seiko and, under the King Seiko name, its direct in-house competition. The Grand Seiko caliber 5646 and this King Seiko caliber 5626 share the same basic architecture; they were differentiated by fine adjustment, features, and final finishing.

King Seiko was therefore never the second choice. It was the more affordable watch based on the same engineering foundation.

"Hi-Beat" – what’s on the dial

The lettering KS HI-BEAT denotes the high oscillation frequency of the movement: 28,800 semi-oscillations per hour, meaning the balance wheel oscillates eight times per second.

The logic behind this is simple. The faster a balance wheel oscillates, the less external disturbances—shocks, changes in position, accelerations while wearing—affect timekeeping. A fast-oscillating balance wheel returns to its rhythm more quickly. The price for this is higher wear and more complex construction, which is why Hi-Beat movements were installed exclusively in top-tier lines at the time of their introduction.

This is visible in the seconds hand: it runs noticeably smoother than in a movement with 18,000 or 21,600 semi-oscillations.

Caliber 5626A

• Automatic with additional manual winding
• Hacking seconds (stops the second hand when pulling the crown) – for second-accurate setting
• 25 jewels, 28,800 semi-oscillations per hour
• Day and date with quick-set
• Day wheel is bilingual, Japanese and English
• Manufactured by Suwa Seikosha, Japan

The bilingual day wheel follows the Japanese calendar convention: Sunday in red, Saturday in blue. A detail not found on European watches.

Front-loading movement

The case back carries an instruction rarely seen: OPEN THRU GLASS, PUSH SET LEVER, PULL STEM.

The movement is not removed from the back, but from the front after removing the crystal. The addition is directed at the watchmaker: the setting lever must be pressed before the winding stem can be pulled.

The structural reason for this is water resistance. A case that is not opened from the back has one less weak point—which is why Seiko did not imprint "WATER RESIST" here, but "WATERPROOF". The price for this was increased effort in the workshop: during every service, the dial side is exposed. This is precisely why many of these watches today bear marks of improper handling on the dial. This is not the case with this example.

The material specification on the case back reads SGP BACK ST. STEEL: SGP stands for Seiko’s own gold-plating process, which was used on the premium lines; the back section is made of stainless steel.

Dial and case

The dial is finished in a light silver tone with a fine grain that scatters light instead of reflecting it—this keeps it highly legible in any lighting. The hour markers are applied, multi-faceted gold batons with sharp edges; at twelve o'clock, they are executed as a double index. Complementing these are slender gold-colored hands and a fine central seconds hand.

The dial is sparsely labeled: SEIKO AUTOMATIC at the top, KS HI-BEAT with the Suwa logo at the bottom. The calendar window at three o'clock is framed in an applied gold border and displays the day of the week and date side-by-side.

The case follows the design language that Taro Tanaka formulated at Seiko as the "Grammar of Design": flat, sharply defined surfaces instead of rounded transitions, angular lugs, and a flat bezel. Tanaka's principle was that every surface should reflect light in a defined direction—which only works as long as the edges remain crisp. The edge lines are preserved here; the watch has not been over-polished.

Condition

Technically flawless. The watch was professionally serviced in Japan in the spring/summer of 2026—fully disassembled, cleaned, oiled, and regulated. The automatic mechanism, manual winding, hacking seconds, and the quick-set for day and date function perfectly.

The dial is very well preserved: uniform grain, lettering complete and sharp, applied indices firm and free of corrosion, the calendar frame intact.

To be frank: The gold plating is relatively heavily worn in several places. This primarily affects the lugs, the case edges, and the bezel edge; on the undersides of the lugs, there are some greenish traces of oxidation. If you are expecting a flawless gold-plated case, this watch is not for you.

Counterbalancing this is what remains intact: the gold medallion on the back with complete embossing, all case back engravings clearly legible, the case edges unpolished, and the dial in excellent condition. For a 56 King Seiko, these are the exact points that determine collector value.

The crystal is clear with slight signs of wear. Fitted is a brown leather strap with a crocodile grain.

Dating

The serial number 910441 allows for dating according to the Seiko scheme: the first digit indicates the last digit of the production year, the second the month. 9 - 1 equals January 1969. The 56KS series was introduced in 1968; this example thus dates from the first full year of production.

Technical specifications

• Brand / Line: King Seiko, Hi-Beat
• Reference: 5626-7000
• Serial number: 910441
• Production date: January 1969
• Movement: Seiko caliber 5626A, automatic with manual winding, 25 jewels, 28,800 A/h, hacking seconds
• Manufacturer: Suwa Seikosha, Japan
• Functions: Hours, minutes, central seconds, day and date with quick-set, bilingual day wheel (Japanese/English)
• Case: Gold-plated (SGP), stainless steel case back, gold medallion with KS insignia, movement removed from the front through the crystal
• Diameter (without crown): 36.1 mm
• Height: 10.4 mm
• Lug-to-lug: 41.6 mm
• Lug width: 18 mm
• Weight (incl. strap): 44 g
• Strap: Brown leather strap with crocodile grain
• Crystal: Acrylic glass
• Service: Spring/summer 2026, Japan – full disassembly, cleaning, oiling, regulation

Who is this for?

For those starting a King Seiko collection. A 56KS Hi-Beat with a preserved gold medallion and untouched case edges in stainless steel regularly costs many times more; the worn gold plating makes this example accessible without missing anything technically or historically.

For anyone looking for a watch that is not supposed to look brand new. The case shows that the watch has been worn for fifty-six years—and the movement runs after the service as if it were just the beginning.

And for collectors who want to represent the Suwa side of Seiko history: this movement shares the basic architecture with the Grand Seiko caliber 5646 from the same production facility.

With a diameter of 36.1 mm, a height of 10.4 mm, and a lug-to-lug of 41.6 mm, it wears discreetly and also fits narrower wrists.

Warranty (used)
This is a used item. The limitation period for claims for defects (statutory warranty) is 12 months from delivery.

Note
As this is a vintage watch, no water resistance can be guaranteed. To protect the movement, the watch should not come into contact with water or moisture.