Seiko Cal. 5638 - 385

The Seiko 5638-385 represents an important milestone in Seiko's 1978 lineup. The Bidirectional bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-df528ccddbc0]

Also known as: Tuna, UFO

Specifications

Movement

Solar

Case Material

Titanium

Case Width

37mm

Case Thickness

12.2mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

100m

Dial Color

Blue Sunburst

Jewels

28j

Frequency

21,600 bph

Power Reserve

66 hours

Year

1978

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