Seiko Cal. 5661 - 378

This Spring Drive model from 1990 features a 36mm Titanium case. Powered by the 5661 caliber with 31j jewels beating at 36,000 bph, it delivers a 41 hours power reserve. [seikata-wm-9f3ae78f0eed]

Also known as: Baby Tuna, Emperor

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

36mm

Case Thickness

14.1mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

160m

Dial Color

Navy

Jewels

31j

Frequency

36,000 bph

Power Reserve

41 hours

Year

1990

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