Seiko Cal. 6640 - 341

This Spring Drive model from 1971 features a 35mm Titanium case. Powered by the 6640 caliber with 21j jewels beating at 36,000 bph, it delivers a 59 hours power reserve. [seikata-wm-9966ff30b8c1]

Also known as: Bullhead

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

35mm

Case Thickness

10.5mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

190m

Dial Color

Navy

Jewels

21j

Frequency

36,000 bph

Power Reserve

59 hours

Year

1971

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