Seiko Cal. 6640 - 446

This Solar model from 1972 features a 44mm Hardlex-Coated Steel case. Powered by the 6640 caliber with 19j jewels beating at 21,600 bph, it delivers a 41 hours power reserve. [seikata-wm-582064503108]

Also known as: Sumo

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

8.7mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Burgundy

Jewels

19j

Frequency

21,600 bph

Power Reserve

41 hours

Year

1972

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