Seiko Cal. 6640 - 700

The Seiko 6640-700 represents an important milestone in Seiko's 1978 lineup. Powered by the 6640 caliber with 33j jewels beating at 36,000 bph, it delivers a 42 hours power reserve. [seikata-wm-e8e1183c9166]

Also known as: Baby Tuna

Specifications

Movement

Kinetic

Case Material

Gold-Plated

Case Width

40mm

Case Thickness

10.0mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

50m

Dial Color

Burgundy

Jewels

33j

Frequency

36,000 bph

Power Reserve

42 hours

Year

1978

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