Seiko Cal. 6640 - 921

The Seiko 6640-921 represents an important milestone in Seiko's 1971 lineup. With its 21mm lug width and 14.4mm profile, it sits comfortably on most wrists. [seikata-wm-31544092583e]

Also known as: Flighty

Specifications

Movement

Automatic

Case Material

Gold-Plated

Case Width

35mm

Case Thickness

14.4mm

Lug Width

21mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

180m

Dial Color

Blue Sunburst

Jewels

18j

Frequency

28,800 bph

Power Reserve

43 hours

Year

1971

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