Seiko Cal. 6635 - 990

The Seiko 6635-990 represents an important milestone in Seiko's 1975 lineup. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 150m of water resistance. [seikata-wm-de1fd77b1b2d]

Also known as: Tuna

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

39mm

Case Thickness

14.5mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

150m

Dial Color

Blue Sunburst

Jewels

35j

Frequency

36,000 bph

Power Reserve

72 hours

Year

1975

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