Seiko Cal. 6640 - 837

The Seiko 6640-837 represents an important milestone in Seiko's 1976 lineup. With its 18mm lug width and 11.8mm profile, it sits comfortably on most wrists. [seikata-wm-7c3279bfcf71]

Also known as: World Timer

Specifications

Movement

Solar

Case Material

Titanium

Case Width

41mm

Case Thickness

11.8mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

70m

Dial Color

Champagne

Jewels

28j

Frequency

36,000 bph

Power Reserve

59 hours

Year

1976

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