Seiko Cal. 6640 - 720

The Seiko 6640-720 represents an important milestone in Seiko's 1984 lineup. The Fixed bezel and 44mm case give it a distinctive presence on the wrist. [seikata-wm-2512e7358c39]

Also known as: Samurai, Bullhead

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

44mm

Case Thickness

10.1mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

40m

Dial Color

Cream

Jewels

27j

Frequency

21,600 bph

Power Reserve

43 hours

Year

1984

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