Seiko Cal. 6631 - 940

This Quartz model from 1975 features a 39mm Two-Tone case. It features a Navy dial protected by a Hardlex crystal and offers 90m of water resistance. [seikata-wm-f1fef6ca1e4a]

Also known as: Turtle, Emperor

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

39mm

Case Thickness

10.8mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

90m

Dial Color

Navy

Jewels

21j

Frequency

28,800 bph

Power Reserve

64 hours

Year

1975

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