Seiko Cal. 3878 - 920

The 3878-920 is a sought-after Spring Drive piece from Seiko's golden era. With its 21mm lug width and 13.5mm profile, it sits comfortably on most wrists. [seikata-wm-50572db4c408]

Also known as: Tuna, Helmet

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

41mm

Case Thickness

13.5mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

60m

Dial Color

Navy

Jewels

19j

Frequency

36,000 bph

Power Reserve

47 hours

Year

1992

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