Seiko Business-A – Automatic (Ref. 8346-9000) (July 1977)

This elegant Seiko Business-A, reference 8346-9000, is a classic model from the late Shōwa era and exemplifies Seiko's design and engineering philosophy of the mid-1970s. It combines precise automatic technology with a clean, functional appearance – created for the modern business environment of that time.

Design & Character

The silver sunburst dial with applied bar indices and finely set dauphine hands gives the watch a harmonious, sophisticated appearance.
The rectangular day-date window at 3 o'clock is framed and slightly recessed – a typical detail of the Business A series.

The stainless steel case is elegantly proportioned, with gently sloping lugs and a finely polished bezel. The screw-down case back bears the following engraving:
“STAINLESS STEEL 8346-9000 WATER PROOF” – a characteristic feature of the early Business A series, which was still equipped with robust seals.

The new brown leather strap with contrasting stitching underlines the classic character of this vintage watch and harmonizes perfectly with the warm glow of the dial.

Technical data

• Model: Seiko Business-A
• Reference: 8346-9000
• Serial number: 77xxxxx
• Production date: July 1977 (Serial number code: 7 7 → 1977 / July)
• Origin: Japan
• Movement: Seiko Caliber 8346A , automatic
• Storage gems: 27 Jewels (Diashock)
• Functions: Hour, minute, central second, day, date
• Power reserve: approx. 43 hours
• Frequency: 21,600 A/h
• Case material: Stainless steel (SS)
• Diameter: 37.3 mm
• Height: 12.7 mm
• Lug-to-lug: 42.8 mm
• Lug width: 19 mm
• Weight (including strap): 54 g
• Glass: slightly curved acrylic glass
• Base: screwed on, “Water Proof” engraving, Ref. 8346-9000
• Crown: signed, at 3 o'clock
• Bracelet: new brown leather strap with quilted stitching
• Clasp: Stainless steel pin buckle

Background & technical significance

The Seiko Business A series was conceived as a bridge between the sportier Seiko 5 line and the more formal Lord Matic range. The Caliber 8346A, introduced in the mid-1970s, was one of the last high-quality in-house automatic movements with 27 jewels before Seiko increasingly transitioned to the later 6300 and 7000 calibers.

The Business A models were characterized by their reliability and timelessly understated aesthetics – ideal for professionals and business people who valued quality but not extravagance.

The “Water Proof” label corresponds to the Japanese standard of the time; from today's point of view, the watch should no longer come into contact with water in order to protect the automatic movement.

Condition

Good, well-maintained vintage condition with slight signs of age.
The dial has a uniform, attractive patina; the indices and hands are original.
The device runs reliably; the date and day of the week change correctly .
The glass is clear, the new leather strap is unworn.

Warranty (used)

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

A notice:
As this is a vintage watch, water resistance cannot be guaranteed. To protect the movement, the watch should not come into contact with water or moisture .