Seiko Cal. 6643 - 990

The Seiko 6643-990 represents an important milestone in Seiko's 1970 lineup. It features a Black dial protected by a Sapphire crystal and offers 60m of water resistance. [seikata-wm-5431f61b4691]

Also known as: Crown, Emperor

Specifications

Movement

Quartz

Case Material

Titanium

Case Width

38mm

Case Thickness

9.5mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

60m

Dial Color

Black

Jewels

23j

Frequency

28,800 bph

Power Reserve

46 hours

Year

1970

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