Seiko Cal. 5631 - 181

The 5631-181 is a sought-after Solar piece from Seiko's golden era. Powered by the 5631 caliber with 20j jewels beating at 28,800 bph, it delivers a 40 hours power reserve. [seikata-wm-68ed1748dc87]

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

41mm

Case Thickness

10.6mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

40m

Dial Color

Navy

Jewels

20j

Frequency

28,800 bph

Power Reserve

40 hours

Year

1967

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