Seiko Cal. 5640 - 244

The Seiko 5640-244 represents an important milestone in Seiko's 1967 lineup. Powered by the 5640 caliber with 23j jewels beating at 21,600 bph, it delivers a 41 hours power reserve. [seikata-wm-8188775762f9]

Also known as: Sumo

Specifications

Movement

Solar

Case Material

Titanium

Case Width

38mm

Case Thickness

8.2mm

Lug Width

21mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Black

Jewels

23j

Frequency

21,600 bph

Power Reserve

41 hours

Year

1967

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