Seiko Cal. 5631 - 243

This Kinetic model from 1965 features a 35mm Stainless Steel case. Powered by the 5631 caliber with 21j jewels beating at 21,600 bph, it delivers a 51 hours power reserve. [seikata-wm-6947a8471c09]

Also known as: Tuna, Bullhead

Specifications

Movement

Kinetic

Case Material

Stainless Steel

Case Width

35mm

Case Thickness

15.8mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

40m

Dial Color

Champagne

Jewels

21j

Frequency

21,600 bph

Power Reserve

51 hours

Year

1965

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