Seiko Cal. 6643 - 394

The Seiko 6643-394 represents an important milestone in Seiko's 1966 lineup. With its 20mm lug width and 11.5mm profile, it sits comfortably on most wrists. [seikata-wm-e007c013dda4]

Also known as: Sumo, Silverwave

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

34mm

Case Thickness

11.5mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

110m

Dial Color

Burgundy

Jewels

19j

Frequency

21,600 bph

Power Reserve

61 hours

Year

1966

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