Seiko Cal. 6640 - 238

The Seiko 6640-238 represents an important milestone in Seiko's 1981 lineup. With its 22mm lug width and 8.8mm profile, it sits comfortably on most wrists. [seikata-wm-7cdb0cf2b6ae]

Also known as: Sumo

Specifications

Movement

Kinetic

Case Material

Stainless Steel

Case Width

40mm

Case Thickness

8.8mm

Lug Width

22mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Black

Jewels

25j

Frequency

28,800 bph

Power Reserve

48 hours

Year

1981

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