Seiko Cal. 5639 - 644

The Seiko 5639-644 represents an important milestone in Seiko's 1985 lineup. The Fixed bezel and 42mm case give it a distinctive presence on the wrist. [seikata-wm-237d576741af]

Also known as: Sumo, Sportsmatic

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

42mm

Case Thickness

13.5mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

80m

Dial Color

Green

Jewels

27j

Frequency

21,600 bph

Power Reserve

62 hours

Year

1985

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