Seiko Cal. 6640 - 668

The Seiko 6640-668 represents an important milestone in Seiko's 1980 lineup. It features a Burgundy dial protected by a Sapphire crystal and offers 150m of water resistance. [seikata-wm-a85e86d8a497]

Also known as: World Timer

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

14.8mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Rotating

Water Resistance

150m

Dial Color

Burgundy

Jewels

24j

Frequency

28,800 bph

Power Reserve

69 hours

Year

1980

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