Seiko Cal. 5641 - 251

This Spring Drive model from 1967 features a 36mm PVD Black case. Powered by the 5641 caliber with 17j jewels beating at 36,000 bph, it delivers a 60 hours power reserve. [seikata-wm-79e49b71ade5]

Also known as: Tuna, UFO

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

36mm

Case Thickness

8.1mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

200m

Dial Color

Champagne

Jewels

17j

Frequency

36,000 bph

Power Reserve

60 hours

Year

1967

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