Seiko Cal. 6639 - 731

The Seiko 6639-731 represents an important milestone in Seiko's 1986 lineup. With its 19mm lug width and 11.3mm profile, it sits comfortably on most wrists. [seikata-wm-47dd2251b899]

Also known as: Silverwave

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

45mm

Case Thickness

11.3mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Blue Sunburst

Jewels

23j

Frequency

36,000 bph

Power Reserve

50 hours

Year

1986

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