Seiko Cal. 6640 - 266

The Seiko 6640-266 represents an important milestone in Seiko's 1978 lineup. Powered by the 6640 caliber with 34j jewels beating at 21,600 bph, it delivers a 40 hours power reserve. [seikata-wm-16bc76177bc2]

Also known as: Rally, Sportsmatic

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

38mm

Case Thickness

9.9mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

60m

Dial Color

Champagne

Jewels

34j

Frequency

21,600 bph

Power Reserve

40 hours

Year

1978

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