Seiko Cal. 6638 - 644

The Seiko 6638-644 represents an important milestone in Seiko's 1980 lineup. The Bidirectional bezel and 45mm case give it a distinctive presence on the wrist. [seikata-wm-f0a2cd52a5f9]

Also known as: Emperor

Specifications

Movement

Quartz

Case Material

Stainless Steel

Case Width

45mm

Case Thickness

13.2mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

70m

Dial Color

Blue Sunburst

Jewels

35j

Frequency

21,600 bph

Power Reserve

62 hours

Year

1980

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