Seiko Cal. 4431 - 521

This Hand-Winding model from 1976 features a 43mm Titanium case. With its 19mm lug width and 9.5mm profile, it sits comfortably on most wrists. [seikata-wm-a8a13529a4ae]

Also known as: Sumo, Helmet

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

43mm

Case Thickness

9.5mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

160m

Dial Color

White

Jewels

30j

Frequency

21,600 bph

Power Reserve

61 hours

Year

1976

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