Seiko Cal. 6391 - 312

Released in 1967, the Cal. 6391 with design code 312 was part of Seiko's domestic market collection. The Rotating bezel and 41mm case give it a distinctive presence on the wrist. [seikata-wm-141ba6bdbff6]

Also known as: Sumo, Helmet

Specifications

Movement

Quartz

Case Material

Titanium

Case Width

41mm

Case Thickness

12.7mm

Lug Width

21mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

130m

Dial Color

Champagne

Jewels

29j

Frequency

36,000 bph

Power Reserve

63 hours

Year

1967

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