Seiko Cal. 4431 - 637

The Seiko 4431-637 represents an important milestone in Seiko's 1980 lineup. It features a Green dial protected by a Acrylic crystal and offers 100m of water resistance. [seikata-wm-a8a6dad2574b]

Also known as: Navigator

Specifications

Movement

Solar

Case Material

Two-Tone

Case Width

36mm

Case Thickness

9.3mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

100m

Dial Color

Green

Jewels

32j

Frequency

36,000 bph

Power Reserve

67 hours

Year

1980

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