Seiko Cal. 6631 - 359

The Seiko 6631-359 represents an important milestone in Seiko's 1987 lineup. With its 20mm lug width and 14.8mm profile, it sits comfortably on most wrists. [seikata-wm-3dd4ee59f540]

Also known as: Tuna, Rally

Specifications

Movement

Solar

Case Material

PVD Black

Case Width

44mm

Case Thickness

14.8mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Silver

Jewels

32j

Frequency

28,800 bph

Power Reserve

38 hours

Year

1987

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