Seiko Cal. 4428 - 740

This Spring Drive model from 1975 features a 42mm PVD Black case. With its 21mm lug width and 9.9mm profile, it sits comfortably on most wrists. [seikata-wm-67fc1751faec]

Also known as: World Timer

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

42mm

Case Thickness

9.9mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Silver

Jewels

28j

Frequency

21,600 bph

Power Reserve

36 hours

Year

1975

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