Seiko Cal. 6640 - 767

Released in 1980, the Cal. 6640 with design code 767 was part of Seiko's domestic market collection. It features a Green dial protected by a Sapphire crystal and offers 40m of water resistance. [seikata-wm-d37e84aa1645]

Also known as: Crown

Specifications

Movement

Solar

Case Material

Gold-Plated

Case Width

34mm

Case Thickness

15.5mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

40m

Dial Color

Green

Jewels

31j

Frequency

36,000 bph

Power Reserve

41 hours

Year

1980

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