Seiko Cal. 6657 - 640

The Seiko 6657-640 represents an important milestone in Seiko's 1973 lineup. Powered by the 6657 caliber with 34j jewels beating at 36,000 bph, it delivers a 62 hours power reserve. [seikata-wm-0765fb6e9799]

Also known as: Flighty

Specifications

Movement

Automatic

Case Material

Gold-Plated

Case Width

43mm

Case Thickness

12.1mm

Lug Width

20mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

180m

Dial Color

White

Jewels

34j

Frequency

36,000 bph

Power Reserve

62 hours

Year

1973

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