Description
Seiko vintage mechanical watch
MADE IN JAPAN
“Seiko” (精工) is a Japanese word meaning “precision,” “exquisite workmanship,” or “refined craftsmanship.”
It comes from the characters:
-
精 (sei) – fine, precise, refined
-
工 (ko) – craft, workmanship
Originally, Seiko’s watchmaking division was called Seikosha (精工舎), meaning “House of Precision.”
The name first appeared on a watch dial in 1924, shortened from Seikosha and keeping the core meaning; the company itself was renamed Hattori Seiko in 1983 and Seiko Corporation in 1990.
So the brand name literally ties directly to the idea of precision engineering—which is exactly what the company wanted to be known for in its watches.
About the Business-A Line
The Business-A dial name appeared during 1967 on Seiko’s 83-series automatics, aimed at the Japanese salaried professional.
It did not replace the Seikomatic-R. The two ran side by side on the same 83-series calibers, the Seikomatic-R badge carrying the older, more formal name and Business-A the one aimed at a younger office buyer; Seiko sold several of the same case references under both. Either way the movement is an automatic with Diashock shock protection, running at 18,000 bph.
The name was deliberately straightforward: “Business” for the white-collar audience it served, “A” for automatic. No clever portmanteau — just a clear statement of purpose for the dress watch of Japan’s post-war business generation.
The 83-series calibers powering the Business-A were a genuine step up from entry-level Seiko offerings: 27 to 30 jewels when most mid-market automatics offered 17–21, with Diashock protecting the balance staff through decades of daily wear. The day-date at 3 o’clock added practical utility without cluttering the dial, with a quickset date; the day is set by cycling the hands past midnight.
The Business-A sat between the Seiko 5 below it and King Seiko above it, and still trades well under either on the second-hand market. Many were sold on period expansion bracelets, and plenty have since been swapped for straps or lost links along the way.
About This Watch
This is a Seiko Business-A, reference 8346-7000, powered by the automatic caliber 8346A with 27 jewels. Its case-back serial number, 7400873, dates production to April 1967 — right at the opening of the Business-A era, with the Seikomatic-R name still in use alongside it.
The watch pairs a warm gray sunburst dial with applied silver-tone baton markers and a framed day-date window at 3 o’clock. The 83-series movement winds itself as you wear it, is protected by Seiko’s Diashock system, and runs at 18,000 bph. It comes on a vintage steel expansion bracelet.
Technical Specifications
- Brand: Seiko
- Line: Business-A
- Reference Number: 8346-7000
- Movement: Automatic, caliber 8346A, 27 jewels
- Serial Number: 7400873
- Production Date: April 1967
- Case Material: Stainless steel
- Case Diameter: 35 mm (excluding crown)
- Dial: Gray sunburst with applied baton markers
- Crystal: Mineral Glass
- Case-back: Stainless steel, engraved “8346-7000 — Water Proof”
- Country of Manufacture: Japan
Condition Report
- Dial: Clean gray sunburst with crisp printing; applied markers bright, no moisture intrusion or major blemishes.
- Case: Light surface scratches consistent with age and wear; retains its original brushed and polished finishing.
- Crystal: Minor surface marks visible at certain angles.
- Bracelet: Vintage steel expansion bracelet, intact and functional with age-appropriate patina.

This watch has recently been serviced by a professional watchmaker and keeps good time.
Comes complete with vintage stainless steel expansion bracelet.

This watch ships from 🇺🇦 Ukraine with tracking number

Why Collectors Want This Watch Today
The Business-A sits in the quiet middle of vintage Seiko collecting — more refined than a Seiko 5, more attainable than a Seikomatic-R or King Seiko — and the market hasn’t fully caught up with it. A 1967 example with an honest gray sunburst dial, a correct 27-jewel 8346A movement, and its period expansion bracelet still intact is exactly the kind of understated dress automatic that rewards the collector who buys before the rest of the market notices.

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We guarantee the item you receive looks and works exactly as advertised — or your money back.

Seiko lug-width matched leather straps — 18 / 19 / 20 mm

About the watch factory
Seiko Group Corporation (セイコーグループ株式会社, Seikō Gurūpu kabushiki gaisha), commonly known as Seiko, is a Japanese maker of watches, clocks, electronic devices, and semiconductors. Founded in 1881 by Kintarō Hattori in Tokyo, Seiko introduced the world’s first commercial quartz wristwatch in 1969.
Seiko is widely known for its wristwatches. Seiko is one of the few watch companies that is fully vertically integrated. Seiko is able to design and develop all the components of a watch, as well as assemble, adjust, inspect and ship them in-house. Seiko’s mechanical watches consist of approximately 200 parts, and the company has the technology and production facilities to design and manufacture all of these parts internally.
Seiko offers one of the widest ranges of watch technologies in the world—quartz, kinetic, solar, mechanical, and Spring Drive—spanning everything from affordable everyday pieces to six-figure haute horlogerie. Over the decades it has launched multiple global brands, including Lorus, Pulsar, and Alba, while elevating its prestige through innovations like Spring Drive, which helped push Seiko into higher-end territory. In 2017, Grand Seiko was spun off into its own standalone luxury brand, while Credor remains part of Seiko’s own lineup, sold primarily in Japan. Seiko’s own global lineup now includes Grand Seiko, King Seiko, Prospex, Astron, Presage, and Seiko 5 Sports.
Among Seiko’s key lines, Seiko 5 (born in 1963) is the gateway mechanical series known for durability and value; Lord Matic defined 1970s style with faceted crystals and colorful dials; Astron remains Seiko’s flagship GPS-solar tech line; Presage focuses on traditional mechanical craftsmanship with enamel and urushi dials; and Prospex delivers professional-grade dive, field, and pilot watches often embraced by enthusiasts. At the top end, Grand Seiko emphasizes precision, Zaratsu polished design, and movements like Spring Drive, while King Seiko—revived in the 2020s—brings back sharp, elegant 1960s styling with modern calibres.
Finally, Credor represents Seiko’s pinnacle of artisanal watchmaking, producing low-volume pieces in precious metals and showcasing Japanese decorative arts and haute complications from the Micro Artist Studio. Beyond watches, Seiko has also produced various electronic devices and, historically, jewelry and eyewear—though those divisions have since shifted to other companies.





















