Seiko Cal. 6639 - 337

This Spring Drive model from 1972 features a 37mm Two-Tone case. The Bidirectional bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-ac2b6a5531ba]

Also known as: UFO

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

37mm

Case Thickness

9.3mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

27j

Frequency

21,600 bph

Power Reserve

68 hours

Year

1972

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