Seiko Cal. 6640 - 918

This Spring Drive model from 1989 features a 36mm Stainless Steel case. With its 20mm lug width and 11.3mm profile, it sits comfortably on most wrists. [seikata-wm-2a193f64bebf]

Also known as: Shogun, Sea Horse

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

36mm

Case Thickness

11.3mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

110m

Dial Color

Blue Sunburst

Jewels

17j

Frequency

21,600 bph

Power Reserve

38 hours

Year

1989

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