Seiko Cal. 6640 - 884

This Spring Drive model from 1980 features a 34mm Titanium case. Powered by the 6640 caliber with 19j jewels beating at 21,600 bph, it delivers a 66 hours power reserve. [seikata-wm-cf2a8b9da2b1]

Also known as: Tuna, Rally

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

34mm

Case Thickness

15.4mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

90m

Dial Color

Black

Jewels

19j

Frequency

21,600 bph

Power Reserve

66 hours

Year

1980

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