Seiko Cal. 6331 - 999

This Spring Drive model from 1968 features a 40mm Gold-Plated case. The Bidirectional bezel and 40mm case give it a distinctive presence on the wrist. [seikata-wm-618315e6e4ae]

Also known as: Tuna, Rally

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

40mm

Case Thickness

8.5mm

Lug Width

19mm

Crystal

Mineral

Bezel

Bidirectional

Water Resistance

70m

Dial Color

Silver

Jewels

26j

Frequency

28,800 bph

Power Reserve

50 hours

Year

1968

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