Seiko Cal. 6643 - 397

The Seiko 6643-397 represents an important milestone in Seiko's 1971 lineup. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 190m of water resistance. [seikata-wm-c8fe30ff96ca]

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

12.9mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

190m

Dial Color

Blue Sunburst

Jewels

26j

Frequency

21,600 bph

Power Reserve

45 hours

Year

1971

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