Seiko Cal. 5638 - 686

This Hand-Winding model from 1976 features a 40mm Titanium case. Powered by the 5638 caliber with 29j jewels beating at 28,800 bph, it delivers a 52 hours power reserve. [seikata-wm-8dad66a66242]

Also known as: UFO, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

40mm

Case Thickness

15.7mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

160m

Dial Color

Green

Jewels

29j

Frequency

28,800 bph

Power Reserve

52 hours

Year

1976

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