Seiko Cal. 4421 - 747

This Hand-Winding model from 1976 features a 40mm PVD Black case. With its 21mm lug width and 15.2mm profile, it sits comfortably on most wrists. [seikata-wm-cbafe6fcd70a]

Also known as: Tuna

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

40mm

Case Thickness

15.2mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

110m

Dial Color

White

Jewels

32j

Frequency

21,600 bph

Power Reserve

48 hours

Year

1976

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