Seiko Cal. 6639 - 921

The Seiko 6639-921 represents an important milestone in Seiko's 1967 lineup. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 190m of water resistance. [seikata-wm-8cac58bd1a9a]

Also known as: Tuna, Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

42mm

Case Thickness

11.7mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

190m

Dial Color

Blue Sunburst

Jewels

36j

Frequency

21,600 bph

Power Reserve

45 hours

Year

1967

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