Seiko Cal. 5631 - 921

This Spring Drive model from 1993 features a 42mm Titanium case. It features a Green dial protected by a Hardlex crystal and offers 30m of water resistance. [seikata-wm-fff8890066f3]

Also known as: World Timer, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

42mm

Case Thickness

10.5mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

30m

Dial Color

Green

Jewels

18j

Frequency

36,000 bph

Power Reserve

55 hours

Year

1993

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