Seiko Cal. 6638 - 917

The Seiko 6638-917 represents an important milestone in Seiko's 1983 lineup. Powered by the 6638 caliber with 31j jewels beating at 21,600 bph, it delivers a 60 hours power reserve. [seikata-wm-a97b182cb67c]

Also known as: UFO

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

15.1mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

130m

Dial Color

Green

Jewels

31j

Frequency

21,600 bph

Power Reserve

60 hours

Year

1983

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