Seiko Cal. 6643 - 637

The 6643-637 is a sought-after Quartz piece from Seiko's golden era. Powered by the 6643 caliber with 25j jewels beating at 21,600 bph, it delivers a 51 hours power reserve. [seikata-wm-6c31964ad017]

Also known as: Emperor, Arnie

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

39mm

Case Thickness

10.7mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

30m

Dial Color

Champagne

Jewels

25j

Frequency

21,600 bph

Power Reserve

51 hours

Year

1974

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