Seiko Cal. 6631 - 817

This Hand-Winding model from 1981 features a 36mm Hardlex-Coated Steel case. With its 20mm lug width and 15.9mm profile, it sits comfortably on most wrists. [seikata-wm-8ccf0bc9364c]

Also known as: Crown, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

15.9mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

70m

Dial Color

Green

Jewels

20j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1981

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