Seiko Cal. 6331 - 309

This Hand-Winding model from 1977 features a 35mm Hardlex-Coated Steel case. The Fixed bezel and 35mm case give it a distinctive presence on the wrist. [seikata-wm-e9e2665abc3a]

Also known as: Golden Tuna, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

11.0mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

17j

Frequency

28,800 bph

Power Reserve

41 hours

Year

1977

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