Seiko Cal. 6640 - 429

This Spring Drive model from 1974 features a 38mm Hardlex-Coated Steel case. It features a Blue Sunburst dial protected by a Sapphire crystal and offers 90m of water resistance. [seikata-wm-35c5774a97ed]

Also known as: UFO

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

11.6mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

90m

Dial Color

Blue Sunburst

Jewels

28j

Frequency

36,000 bph

Power Reserve

64 hours

Year

1974

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