Seiko Cal. 5631 - 721

The Seiko 5631-721 represents an important milestone in Seiko's 1998 lineup. Powered by the 5631 caliber with 25j jewels beating at 21,600 bph, it delivers a 39 hours power reserve. [seikata-wm-bac65930cef5]

Specifications

Movement

Solar

Case Material

Gold-Plated

Case Width

34mm

Case Thickness

11.1mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

80m

Dial Color

Silver

Jewels

25j

Frequency

21,600 bph

Power Reserve

39 hours

Year

1998

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