Seiko Cal. 4427 - 640

The Seiko 4427-640 represents an important milestone in Seiko's 1974 lineup. The Fixed bezel and 39mm case give it a distinctive presence on the wrist. [seikata-wm-f0243d723bb0]

Also known as: Tuna, Crown

Specifications

Movement

Automatic

Case Material

Two-Tone

Case Width

39mm

Case Thickness

10.6mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

40m

Dial Color

Blue Sunburst

Jewels

30j

Frequency

21,600 bph

Power Reserve

43 hours

Year

1974

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