Seiko Cal. 5631 - 308

The Seiko 5631-308 represents an important milestone in Seiko's 1971 lineup. With its 18mm lug width and 11.1mm profile, it sits comfortably on most wrists. [seikata-wm-731ed2c884bc]

Also known as: Monster, Bullhead

Specifications

Movement

Quartz

Case Material

Gold-Plated

Case Width

41mm

Case Thickness

11.1mm

Lug Width

18mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

130m

Dial Color

Navy

Jewels

26j

Frequency

36,000 bph

Power Reserve

59 hours

Year

1971

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