Seiko Cal. 6631 - 878

This Automatic model from 1974 features a 39mm Titanium case. Powered by the 6631 caliber with 32j jewels beating at 28,800 bph, it delivers a 54 hours power reserve. [seikata-wm-a78ef65ec69f]

Also known as: Bellmatic, Sea Horse

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

39mm

Case Thickness

14.5mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

130m

Dial Color

Cream

Jewels

32j

Frequency

28,800 bph

Power Reserve

54 hours

Year

1974

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