Seiko Cal. 5640 - 425

This Spring Drive model from 1971 features a 41mm Stainless Steel case. Powered by the 5640 caliber with 17j jewels beating at 21,600 bph, it delivers a 69 hours power reserve. [seikata-wm-e069108d1f30]

Also known as: Bullhead

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

41mm

Case Thickness

15.5mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Rotating

Water Resistance

90m

Dial Color

Green

Jewels

17j

Frequency

21,600 bph

Power Reserve

69 hours

Year

1971

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