Seiko Cal. 6643 - 837

This Hand-Winding model from 1973 features a 39mm PVD Black case. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 80m of water resistance. [seikata-wm-97902802eba9]

Also known as: Sea Horse, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

39mm

Case Thickness

11.2mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

80m

Dial Color

Blue Sunburst

Jewels

20j

Frequency

21,600 bph

Power Reserve

52 hours

Year

1973

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