Seiko Cal. 5640 - 681

The Seiko 5640-681 represents an important milestone in Seiko's 1984 lineup. Powered by the 5640 caliber with 30j jewels beating at 36,000 bph, it delivers a 63 hours power reserve. [seikata-wm-2927cb7b4e5f]

Also known as: Shogun, UFO

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

14.0mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

70m

Dial Color

Cream

Jewels

30j

Frequency

36,000 bph

Power Reserve

63 hours

Year

1984

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