Seiko Cal. 6631 - 964

The Seiko 6631-964 represents an important milestone in Seiko's 1991 lineup. With its 18mm lug width and 10.5mm profile, it sits comfortably on most wrists. [seikata-wm-93b90c074501]

Also known as: Helmet

Specifications

Movement

Solar

Case Material

Two-Tone

Case Width

35mm

Case Thickness

10.5mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

200m

Dial Color

Silver

Jewels

35j

Frequency

28,800 bph

Power Reserve

53 hours

Year

1991

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