Seiko Cal. 6640 - 771

The Seiko 6640-771 represents an important milestone in Seiko's 1984 lineup. Powered by the 6640 caliber with 27j jewels beating at 21,600 bph, it delivers a 40 hours power reserve. [seikata-wm-b0b7bfc05705]

Also known as: World Timer, Flighty

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

39mm

Case Thickness

11.7mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Green

Jewels

27j

Frequency

21,600 bph

Power Reserve

40 hours

Year

1984

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