Seiko Cal. 4428 - 637

The Seiko 4428-637 represents an important milestone in Seiko's 1970 lineup. It features a Silver dial protected by a Hardlex crystal and offers 130m of water resistance. [seikata-wm-8289808d46ab]

Also known as: Arnie

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

10.9mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

130m

Dial Color

Silver

Jewels

24j

Frequency

36,000 bph

Power Reserve

72 hours

Year

1970

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