Seiko Cal. 5640 - 138

This Spring Drive model from 1973 features a 34mm Two-Tone case. It features a Navy dial protected by a Hardlex crystal and offers 190m of water resistance. [seikata-wm-8743bb90bdab]

Also known as: Turtle, Sumo

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

34mm

Case Thickness

8.8mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

190m

Dial Color

Navy

Jewels

26j

Frequency

21,600 bph

Power Reserve

59 hours

Year

1973

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