Seiko Cal. 6643 - 420

The Seiko 6643-420 represents an important milestone in Seiko's 1973 lineup. The Bidirectional bezel and 40mm case give it a distinctive presence on the wrist. [seikata-wm-2d97120d2b1d]

Also known as: Baby Tuna

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

40mm

Case Thickness

15.8mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

170m

Dial Color

Green

Jewels

35j

Frequency

36,000 bph

Power Reserve

45 hours

Year

1973

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