Seiko Cal. 6640 - 923

The Seiko 6640-923 represents an important milestone in Seiko's 1983 lineup. With its 20mm lug width and 9.2mm profile, it sits comfortably on most wrists. [seikata-wm-dcd17572f389]

Also known as: Sportsmatic, World Timer

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

46mm

Case Thickness

9.2mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

50m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

21,600 bph

Power Reserve

58 hours

Year

1983

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