Seiko Cal. 6640 - 856

The Seiko 6640-856 represents an important milestone in Seiko's 1966 lineup. Powered by the 6640 caliber with 19j jewels beating at 36,000 bph, it delivers a 39 hours power reserve. [seikata-wm-592d54fef11c]

Also known as: Sportsmatic

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

46mm

Case Thickness

8.5mm

Lug Width

19mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

130m

Dial Color

Cream

Jewels

19j

Frequency

36,000 bph

Power Reserve

39 hours

Year

1966

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