Seiko Cal. 6640 - 791

The 6640-791 is a sought-after Spring Drive piece from Seiko's golden era. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 170m of water resistance. [seikata-wm-f05be11347a1]

Also known as: Bellmatic

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

42mm

Case Thickness

9.0mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

170m

Dial Color

Blue Sunburst

Jewels

32j

Frequency

36,000 bph

Power Reserve

42 hours

Year

1966

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