Seiko Cal. 6643 - 900

This Hand-Winding model from 1981 features a 41mm Gold-Plated case. It features a Blue Sunburst dial protected by a Sapphire crystal and offers 110m of water resistance. [seikata-wm-9a58b9cee9cc]

Also known as: Tuna

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

41mm

Case Thickness

9.4mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

110m

Dial Color

Blue Sunburst

Jewels

24j

Frequency

28,800 bph

Power Reserve

66 hours

Year

1981

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