Seiko Cal. 6640 - 756

The Seiko 6640-756 represents an important milestone in Seiko's 1967 lineup. Powered by the 6640 caliber with 26j jewels beating at 36,000 bph, it delivers a 50 hours power reserve. [seikata-wm-55ba0852f1be]

Also known as: UFO, Rally

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

41mm

Case Thickness

15.8mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

30m

Dial Color

Champagne

Jewels

26j

Frequency

36,000 bph

Power Reserve

50 hours

Year

1967

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