Seiko Cal. 5631 - 431

Released in 1987, the Cal. 5631 with design code 431 was part of Seiko's domestic market collection. Powered by the 5631 caliber with 24j jewels beating at 36,000 bph, it delivers a 50 hours power reserve. [seikata-wm-851d3ed9af6b]

Also known as: Bullhead

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

38mm

Case Thickness

13.0mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Navy

Jewels

24j

Frequency

36,000 bph

Power Reserve

50 hours

Year

1987

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