Seiko Cal. 6631 - 904

This Spring Drive model from 1999 features a 42mm Stainless Steel case. The Inner Rotating bezel and 42mm case give it a distinctive presence on the wrist. [seikata-wm-e3eb2aeaa8cb]

Also known as: Monster, Rally

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

42mm

Case Thickness

11.8mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Navy

Jewels

26j

Frequency

21,600 bph

Power Reserve

53 hours

Year

1999

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