Seiko Cal. 5631 - 921

The 5631-921 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 5631 caliber with 26j jewels beating at 36,000 bph, it delivers a 71 hours power reserve. [seikata-wm-fbdf07983db3]

Also known as: Bullhead, Rally

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

42mm

Case Thickness

11.1mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

110m

Dial Color

Cream

Jewels

26j

Frequency

36,000 bph

Power Reserve

71 hours

Year

1991

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