Seiko Cal. 6643 - 655

This Spring Drive model from 1978 features a 42mm PVD Black case. It features a Champagne dial protected by a Acrylic crystal and offers 140m of water resistance. [seikata-wm-91684f276d01]

Also known as: Tuna, UFO

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

42mm

Case Thickness

14.1mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Bidirectional

Water Resistance

140m

Dial Color

Champagne

Jewels

26j

Frequency

28,800 bph

Power Reserve

57 hours

Year

1978

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