Seiko Cal. 6640 - 835

The Seiko 6640-835 represents an important milestone in Seiko's 1973 lineup. The Bidirectional bezel and 38mm case give it a distinctive presence on the wrist. [seikata-wm-98101a3a1cf8]

Also known as: Shogun, Baby Tuna

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

38mm

Case Thickness

14.8mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

100m

Dial Color

Black

Jewels

34j

Frequency

36,000 bph

Power Reserve

69 hours

Year

1973

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