Seiko Cal. 6637 - 328

This Spring Drive model from 1991 features a 41mm Stainless Steel case. With its 20mm lug width and 10.7mm profile, it sits comfortably on most wrists. [seikata-wm-4d1b8439341c]

Also known as: World Timer

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

41mm

Case Thickness

10.7mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

50m

Dial Color

Black

Jewels

31j

Frequency

36,000 bph

Power Reserve

61 hours

Year

1991

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