Seiko Cal. 6631 - 988

The Seiko 6631-988 represents an important milestone in Seiko's 1988 lineup. Powered by the 6631 caliber with 35j jewels beating at 36,000 bph, it delivers a 41 hours power reserve. [seikata-wm-e5ce5eb3ea9a]

Also known as: UFO, Flighty

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

39mm

Case Thickness

8.1mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

120m

Dial Color

Silver

Jewels

35j

Frequency

36,000 bph

Power Reserve

41 hours

Year

1988

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