Seiko Cal. 5640 - 839

The Seiko 5640-839 represents an important milestone in Seiko's 1976 lineup. With its 21mm lug width and 15.5mm profile, it sits comfortably on most wrists. [seikata-wm-266f6c673735]

Also known as: Sea Horse, Crown

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

15.5mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

120m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

36,000 bph

Power Reserve

45 hours

Year

1976

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