Seiko Cal. 6631 - 491

This Spring Drive model from 1973 features a 40mm Stainless Steel case. The Coin-Edge bezel and 40mm case give it a distinctive presence on the wrist. [seikata-wm-cb913bcdff86]

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

40mm

Case Thickness

12.8mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

60m

Dial Color

Black

Jewels

29j

Frequency

36,000 bph

Power Reserve

49 hours

Year

1973

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