Seiko Cal. 5631 - 138

This Quartz model from 1971 features a 34mm Stainless Steel case. With its 21mm lug width and 11.5mm profile, it sits comfortably on most wrists. [seikata-wm-8ed8d00a1951]

Also known as: Helmet, Emperor

Specifications

Movement

Quartz

Case Material

Stainless Steel

Case Width

34mm

Case Thickness

11.5mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

40m

Dial Color

Navy

Jewels

23j

Frequency

28,800 bph

Power Reserve

36 hours

Year

1971

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