Seiko Cal. 6643 - 728

This Quartz model from 1980 features a 39mm PVD Black case. The Inner Rotating bezel and 39mm case give it a distinctive presence on the wrist. [seikata-wm-fe032bd2179d]

Also known as: Monster

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

39mm

Case Thickness

9.3mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

White

Jewels

34j

Frequency

21,600 bph

Power Reserve

72 hours

Year

1980

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