Seiko Cal. 6631 - 790

The 6631-790 is a sought-after Hand-Winding piece from Seiko's golden era. Powered by the 6631 caliber with 33j jewels beating at 21,600 bph, it delivers a 40 hours power reserve. [seikata-wm-1e0ab169ea9f]

Also known as: Monster, Shogun

Specifications

Movement

Hand-Winding

Case Material

Stainless Steel

Case Width

34mm

Case Thickness

12.7mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

180m

Dial Color

Cream

Jewels

33j

Frequency

21,600 bph

Power Reserve

40 hours

Year

1965

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