Seiko Cal. 6640 - 304

This Solar model from 1970 features a 37mm Gold-Plated case. With its 22mm lug width and 10.7mm profile, it sits comfortably on most wrists. [seikata-wm-e6d5e9abe38f]

Also known as: Bullhead, Emperor

Specifications

Movement

Solar

Case Material

Gold-Plated

Case Width

37mm

Case Thickness

10.7mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

180m

Dial Color

Blue Sunburst

Jewels

21j

Frequency

36,000 bph

Power Reserve

53 hours

Year

1970

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