Seiko Cal. 6631 - 998

The Seiko 6631-998 represents an important milestone in Seiko's 1980 lineup. Powered by the 6631 caliber with 19j jewels beating at 36,000 bph, it delivers a 54 hours power reserve. [seikata-wm-3087a5c9a973]

Also known as: Monster, Emperor

Specifications

Movement

Hand-Winding

Case Material

Stainless Steel

Case Width

44mm

Case Thickness

14.3mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

140m

Dial Color

Green

Jewels

19j

Frequency

36,000 bph

Power Reserve

54 hours

Year

1980

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