Seiko Cal. 5638 - 604

The Seiko 5638-604 represents an important milestone in Seiko's 1969 lineup. Powered by the 5638 caliber with 25j jewels beating at 28,800 bph, it delivers a 48 hours power reserve. [seikata-wm-d7d43b749dfa]

Also known as: Sumo, World Timer

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

39mm

Case Thickness

13.9mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

100m

Dial Color

Burgundy

Jewels

25j

Frequency

28,800 bph

Power Reserve

48 hours

Year

1969

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