Seiko Cal. 6638 - 991

The Seiko 6638-991 represents an important milestone in Seiko's 1992 lineup. Powered by the 6638 caliber with 27j jewels beating at 28,800 bph, it delivers a 70 hours power reserve. [seikata-wm-aa2edd7d008a]

Also known as: Crown, Emperor

Specifications

Movement

Automatic

Case Material

Stainless Steel

Case Width

46mm

Case Thickness

15.2mm

Lug Width

21mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

150m

Dial Color

Black

Jewels

27j

Frequency

28,800 bph

Power Reserve

70 hours

Year

1992

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