Seiko Cal. 4431 - 287

This Hand-Winding model from 1976 features a 35mm PVD Black case. The Inner Rotating bezel and 35mm case give it a distinctive presence on the wrist. [seikata-wm-2acd89ad9b7a]

Also known as: Sumo, UFO

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

35mm

Case Thickness

15.9mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

60m

Dial Color

Cream

Jewels

21j

Frequency

21,600 bph

Power Reserve

57 hours

Year

1976

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