Seiko Cal. 6640 - 743

The Seiko 6640-743 represents an important milestone in Seiko's 1967 lineup. Powered by the 6640 caliber with 25j jewels beating at 21,600 bph, it delivers a 69 hours power reserve. [seikata-wm-c86aa9d9e96d]

Also known as: Flighty

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

35mm

Case Thickness

10.2mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

100m

Dial Color

Burgundy

Jewels

25j

Frequency

21,600 bph

Power Reserve

69 hours

Year

1967

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