Seiko Cal. 6640 - 476

The Seiko 6640-476 represents an important milestone in Seiko's 1976 lineup. The Bidirectional bezel and 43mm case give it a distinctive presence on the wrist. [seikata-wm-4fa4af32dd44]

Also known as: Turtle, Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

43mm

Case Thickness

15.9mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

36,000 bph

Power Reserve

51 hours

Year

1976

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