Seiko Cal. 4420 - 728

The Seiko 4420-728 represents an important milestone in Seiko's 1986 lineup. It features a Green dial protected by a Hardlex crystal and offers 40m of water resistance. [seikata-wm-04b06506f216]

Also known as: Tuna, Arnie

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

15.9mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Green

Jewels

19j

Frequency

36,000 bph

Power Reserve

36 hours

Year

1986

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