Seiko Cal. 6640 - 937

The Seiko 6640-937 represents an important milestone in Seiko's 1988 lineup. It features a Blue Sunburst dial protected by a Mineral crystal and offers 180m of water resistance. [seikata-wm-4e29afb9da75]

Also known as: Rally

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

9.5mm

Lug Width

22mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

180m

Dial Color

Blue Sunburst

Jewels

31j

Frequency

36,000 bph

Power Reserve

40 hours

Year

1988

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