Seiko Cal. 6640 - 900

This Hand-Winding model from 1997 features a 34mm Titanium case. With its 18mm lug width and 11.5mm profile, it sits comfortably on most wrists. [seikata-wm-28abc8b6acb4]

Also known as: Bullhead, Crown

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

34mm

Case Thickness

11.5mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

80m

Dial Color

White

Jewels

29j

Frequency

21,600 bph

Power Reserve

47 hours

Year

1997

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