Seiko Cal. 6631 - 381

The Seiko 6631-381 represents an important milestone in Seiko's 1971 lineup. The Coin-Edge bezel and 36mm case give it a distinctive presence on the wrist. [seikata-wm-549a5c6f7181]

Also known as: Rally

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

36mm

Case Thickness

15.2mm

Lug Width

18mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

160m

Dial Color

Navy

Jewels

32j

Frequency

28,800 bph

Power Reserve

68 hours

Year

1971

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