Seiko Cal. 5631 - 902

The Seiko 5631-902 represents an important milestone in Seiko's 1971 lineup. Powered by the 5631 caliber with 21j jewels beating at 36,000 bph, it delivers a 67 hours power reserve. [seikata-wm-dc345b012ad7]

Also known as: UFO, Rally

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

42mm

Case Thickness

10.9mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Rotating

Water Resistance

150m

Dial Color

Green

Jewels

21j

Frequency

36,000 bph

Power Reserve

67 hours

Year

1971

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