Seiko Cal. 6640 - 240

Released in 1970, the Cal. 6640 with design code 240 was part of Seiko's domestic market collection. With its 20mm lug width and 10.4mm profile, it sits comfortably on most wrists. [seikata-wm-a1dca96fa8ee]

Also known as: Monster, Flighty

Specifications

Movement

Kinetic

Case Material

Stainless Steel

Case Width

34mm

Case Thickness

10.4mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

170m

Dial Color

Cream

Jewels

34j

Frequency

28,800 bph

Power Reserve

46 hours

Year

1970

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