Seiko Cal. 6631 - 156

This Spring Drive model from 1975 features a 38mm Titanium case. With its 21mm lug width and 14.3mm profile, it sits comfortably on most wrists. [seikata-wm-3037f2317b8e]

Also known as: Turtle, Arnie

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

38mm

Case Thickness

14.3mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

130m

Dial Color

Cream

Jewels

32j

Frequency

36,000 bph

Power Reserve

54 hours

Year

1975

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