Seiko Cal. 4423 - 657

The Seiko 4423-657 represents an important milestone in Seiko's 1975 lineup. It features a Blue Sunburst dial protected by a Hardlex crystal and offers 30m of water resistance. [seikata-wm-5b1df69f9e95]

Also known as: Tuna

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

45mm

Case Thickness

9.1mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

21,600 bph

Power Reserve

70 hours

Year

1975

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