Seiko Cal. 6631 - 814

The Seiko 6631-814 represents an important milestone in Seiko's 1986 lineup. Powered by the 6631 caliber with 18j jewels beating at 21,600 bph, it delivers a 41 hours power reserve. [seikata-wm-dcd80f3b79eb]

Also known as: Tuna, Bellmatic

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

37mm

Case Thickness

15.0mm

Lug Width

19mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Burgundy

Jewels

18j

Frequency

21,600 bph

Power Reserve

41 hours

Year

1986

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