Seiko Cal. 6640 - 879

This Spring Drive model from 1992 features a 36mm Hardlex-Coated Steel case. It features a Black dial protected by a Hardlex crystal and offers 40m of water resistance. [seikata-wm-acdf2fba97dc]

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

8.2mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Black

Jewels

25j

Frequency

28,800 bph

Power Reserve

71 hours

Year

1992

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