Seiko Cal. 5631 - 321

This Spring Drive model from 1965 features a 36mm Gold-Plated case. Powered by the 5631 caliber with 34j jewels beating at 28,800 bph, it delivers a 44 hours power reserve. [seikata-wm-9a7e1a740308]

Also known as: Sportsmatic

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

36mm

Case Thickness

12.6mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

40m

Dial Color

Champagne

Jewels

34j

Frequency

28,800 bph

Power Reserve

44 hours

Year

1965

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