Seiko Cal. 5631 - 307

Released in 1988, the Cal. 5631 with design code 307 was part of Seiko's domestic market collection. With its 22mm lug width and 13.7mm profile, it sits comfortably on most wrists. [seikata-wm-fe34bbf12ced]

Also known as: Baby Tuna

Specifications

Movement

Quartz

Case Material

Gold-Plated

Case Width

38mm

Case Thickness

13.7mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Black

Jewels

34j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1988

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