Seiko Cal. 6631 - 728

This Automatic model from 1974 features a 40mm Gold-Plated case. Powered by the 6631 caliber with 33j jewels beating at 36,000 bph, it delivers a 65 hours power reserve. [seikata-wm-d339e7b68f06]

Also known as: Golden Tuna

Specifications

Movement

Automatic

Case Material

Gold-Plated

Case Width

40mm

Case Thickness

12.4mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

180m

Dial Color

Green

Jewels

33j

Frequency

36,000 bph

Power Reserve

65 hours

Year

1974

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