Seiko Cal. 6631 - 478

Released in 1987, the Cal. 6631 with design code 478 was part of Seiko's domestic market collection. Powered by the 6631 caliber with 24j jewels beating at 21,600 bph, it delivers a 64 hours power reserve. [seikata-wm-0ad66970def9]

Also known as: Turtle, Helmet

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

35mm

Case Thickness

8.6mm

Lug Width

19mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

160m

Dial Color

Green

Jewels

24j

Frequency

21,600 bph

Power Reserve

64 hours

Year

1987

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