Seiko Cal. 6640 - 184

The Seiko 6640-184 represents an important milestone in Seiko's 1967 lineup. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 140m of water resistance. [seikata-wm-071d7ed6bc7a]

Also known as: Sumo

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

34mm

Case Thickness

14.4mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

140m

Dial Color

Blue Sunburst

Jewels

31j

Frequency

21,600 bph

Power Reserve

62 hours

Year

1967

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