Seiko Cal. 5638 - 641

This Automatic model from 1976 features a 40mm Titanium case. Powered by the 5638 caliber with 31j jewels beating at 36,000 bph, it delivers a 38 hours power reserve. [seikata-wm-dbdd776e1633]

Also known as: Bellmatic, Sea Horse

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

40mm

Case Thickness

10.5mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Silver

Jewels

31j

Frequency

36,000 bph

Power Reserve

38 hours

Year

1976

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