Seiko Cal. 5691 - 937

This Spring Drive model from 1979 features a 39mm Titanium case. The Bidirectional bezel and 39mm case give it a distinctive presence on the wrist. [seikata-wm-8720810a1a4b]

Also known as: Sumo, Golden Tuna

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

39mm

Case Thickness

9.9mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Burgundy

Jewels

19j

Frequency

28,800 bph

Power Reserve

36 hours

Year

1979

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