Seiko Cal. 5631 - 668

This Quartz model from 1970 features a 37mm Two-Tone case. It features a Cream dial protected by a Sapphire crystal and offers 100m of water resistance. [seikata-wm-d118b7675ead]

Also known as: Helmet

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

37mm

Case Thickness

9.2mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

100m

Dial Color

Cream

Jewels

35j

Frequency

28,800 bph

Power Reserve

60 hours

Year

1970

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