Seiko Cal. 6631 - 660

Released in 1978, the Cal. 6631 with design code 660 was part of Seiko's domestic market collection. The Bidirectional bezel and 39mm case give it a distinctive presence on the wrist. [seikata-wm-ce1bbd332f03]

Also known as: Arnie

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

39mm

Case Thickness

13.7mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

120m

Dial Color

Blue Sunburst

Jewels

18j

Frequency

36,000 bph

Power Reserve

71 hours

Year

1978

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