Seiko Cal. 5681 - 291

The Seiko 5681-291 represents an important milestone in Seiko's 1971 lineup. With its 20mm lug width and 12.3mm profile, it sits comfortably on most wrists. [seikata-wm-0a66bd53a550]

Also known as: Tuna, Helmet

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

12.3mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

180m

Dial Color

Navy

Jewels

18j

Frequency

28,800 bph

Power Reserve

41 hours

Year

1971

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