Seiko Cal. 6638 - 423

This Quartz model from 1986 features a 39mm Hardlex-Coated Steel case. The Bidirectional bezel and 39mm case give it a distinctive presence on the wrist. [seikata-wm-6f247c9acd9b]

Also known as: Sumo

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

39mm

Case Thickness

15.0mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

140m

Dial Color

Cream

Jewels

22j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1986

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