Seiko Cal. 5639 - 678

The Seiko 5639-678 represents an important milestone in Seiko's 1991 lineup. Powered by the 5639 caliber with 36j jewels beating at 21,600 bph, it delivers a 65 hours power reserve. [seikata-wm-9cc3f89f897c]

Also known as: Sumo, Bellmatic

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

43mm

Case Thickness

9.8mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

60m

Dial Color

Champagne

Jewels

36j

Frequency

21,600 bph

Power Reserve

65 hours

Year

1991

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