Seiko Cal. 6640 - 687

The 6640-687 is a sought-after Hand-Winding piece from Seiko's golden era. With its 21mm lug width and 13.2mm profile, it sits comfortably on most wrists. [seikata-wm-d93cb9661ce2]

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

13.2mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

170m

Dial Color

White

Jewels

27j

Frequency

28,800 bph

Power Reserve

52 hours

Year

1966

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