Seiko Cal. 6640 - 198

Released in 1967, the Cal. 6640 with design code 198 was part of Seiko's domestic market collection. With its 20mm lug width and 12.6mm profile, it sits comfortably on most wrists. [seikata-wm-7cb84bad9515]

Also known as: Navigator, Emperor

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

42mm

Case Thickness

12.6mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

140m

Dial Color

Black

Jewels

28j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1967

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