Seiko Cal. 5640 - 681

The Seiko 5640-681 represents an important milestone in Seiko's 1989 lineup. Powered by the 5640 caliber with 26j jewels beating at 21,600 bph, it delivers a 65 hours power reserve. [seikata-wm-e0bc57f89233]

Also known as: Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

12.1mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

150m

Dial Color

Blue Sunburst

Jewels

26j

Frequency

21,600 bph

Power Reserve

65 hours

Year

1989

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