Seiko Cal. 6638 - 745

This Spring Drive model from 1973 features a 38mm Titanium case. It features a Black dial protected by a Acrylic crystal and offers 120m of water resistance. [seikata-wm-a143746e13f5]

Also known as: Tuna, Bellmatic

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

38mm

Case Thickness

11.5mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

120m

Dial Color

Black

Jewels

31j

Frequency

21,600 bph

Power Reserve

69 hours

Year

1973

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