Seiko Cal. 6639 - 478

This Solar model from 1997 features a 40mm Hardlex-Coated Steel case. Powered by the 6639 caliber with 21j jewels beating at 21,600 bph, it delivers a 62 hours power reserve. [seikata-wm-7df2b7d7f58d]

Also known as: Sumo, Helmet

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

9.1mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

30m

Dial Color

White

Jewels

21j

Frequency

21,600 bph

Power Reserve

62 hours

Year

1997

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