Seiko Cal. 5640 - 556

This Spring Drive model from 1986 features a 34mm Stainless Steel case. Powered by the 5640 caliber with 21j jewels beating at 21,600 bph, it delivers a 42 hours power reserve. [seikata-wm-5a0698bae34f]

Also known as: World Timer

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

34mm

Case Thickness

12.6mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

70m

Dial Color

Silver

Jewels

21j

Frequency

21,600 bph

Power Reserve

42 hours

Year

1986

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