Seiko Cal. 6640 - 307

The Seiko 6640-307 represents an important milestone in Seiko's 1994 lineup. The Coin-Edge bezel and 34mm case give it a distinctive presence on the wrist. [seikata-wm-496374818734]

Also known as: Sumo, Rally

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

34mm

Case Thickness

15.5mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

180m

Dial Color

Burgundy

Jewels

36j

Frequency

21,600 bph

Power Reserve

38 hours

Year

1994

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