Description

A proper 1970s JDM Seiko with colour: the blue sunburst 5 Actus SS dial, 25-jewel automatic movement, Kanji day wheel and that chunky late-vintage Seiko case shape.

This is the blue-dial version of the Seiko 5 Actus SS 6106-8660, a great example of Seiko’s colourful 1970s domestic-market. The blue sunburst dial shifts beautifully in the light, with applied baton markers, framed day/date window.

Overview

• Model / case code: Seiko 6106-8660, Seiko 5 Actus SS
• Serial number: 404684 (October 1974)
• Dial: blue sunburst
• Movement: Seiko 6106 automatic, 25 jewels
• Functions: time, central seconds, day/date
• Caseback: stainless steel, Water Resistant, Japan-U
• Service: April 2026 with new seals and pressure tested to 3ATM
• Running condition: Running well
• Included: Watch only

Condition

• Crystal: Clean, and crisp
• Case: Light wear
• Dial/hands: blue sunburst dial, batons
• Strap: black leather strap fitted. 

Measured specifications

• Case diameter (excluding crown): 37 mm
• Lug-to-lug: 41 mm  
• Thickness: 11 mm
• Lug width: 18 mm

Functions / operation check

• Timekeeping: [OK]
• Day/date change: [OK] Kanji/English

About this model: 

The 5 Actus line has a reliable automatic movement, interesting Japanese-market dial variants, and enough design personality to feel very different from modern reissues. The 6106-8660 wears compact but with real wrist presence thanks to the cushion-style case and broad dial opening.

Important notes

Vintage watch sold as described; please review photos carefully (they form part of the description). Has had seals replaced and serviced in April 2026 but water resistance is not guaranteed.