Seiko Cal. 5690 - 640

The Seiko 5690-640 represents an important milestone in Seiko's 1991 lineup. Powered by the 5690 caliber with 25j jewels beating at 21,600 bph, it delivers a 58 hours power reserve. [seikata-wm-0c6ca11ed3dc]

Also known as: Bullhead, Emperor

Specifications

Movement

Solar

Case Material

Titanium

Case Width

45mm

Case Thickness

9.6mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

110m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

21,600 bph

Power Reserve

58 hours

Year

1991

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