Seiko Cal. 5641 - 636

The Seiko 5641-636 represents an important milestone in Seiko's 1974 lineup. The Coin-Edge bezel and 34mm case give it a distinctive presence on the wrist. [seikata-wm-e74f9a831878]

Also known as: UFO, World Timer

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

10.2mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

90m

Dial Color

Blue Sunburst

Jewels

18j

Frequency

28,800 bph

Power Reserve

72 hours

Year

1974

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