Seiko Cal. 6650 - 640

The Seiko 6650-640 represents an important milestone in Seiko's 1979 lineup. Powered by the 6650 caliber with 25j jewels beating at 21,600 bph, it delivers a 45 hours power reserve. [seikata-wm-d0ac4cc2abf4]

Also known as: Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

41mm

Case Thickness

10.3mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

140m

Dial Color

Burgundy

Jewels

25j

Frequency

21,600 bph

Power Reserve

45 hours

Year

1979

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