Seiko Cal. 5631 - 399

The Seiko 5631-399 represents an important milestone in Seiko's 1988 lineup. It features a Green dial protected by a Hardlex crystal and offers 150m of water resistance. [seikata-wm-4a80eb964666]

Also known as: Turtle, UFO

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

36mm

Case Thickness

9.3mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Green

Jewels

20j

Frequency

28,800 bph

Power Reserve

62 hours

Year

1988

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