Seiko Cal. 6644 - 831

The Seiko 6644-831 represents an important milestone in Seiko's 1978 lineup. Powered by the 6644 caliber with 34j jewels beating at 21,600 bph, it delivers a 49 hours power reserve. [seikata-wm-1e2cf9a83675]

Also known as: Helmet

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

43mm

Case Thickness

12.6mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

170m

Dial Color

White

Jewels

34j

Frequency

21,600 bph

Power Reserve

49 hours

Year

1978

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