Seiko Cal. 6631 - 591

This Automatic model from 1965 features a 34mm Gold-Plated case. Powered by the 6631 caliber with 23j jewels beating at 28,800 bph, it delivers a 67 hours power reserve. [seikata-wm-98bdb403d01c]

Also known as: UFO

Specifications

Movement

Automatic

Case Material

Gold-Plated

Case Width

34mm

Case Thickness

9.0mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

70m

Dial Color

Silver

Jewels

23j

Frequency

28,800 bph

Power Reserve

67 hours

Year

1965

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