Seiko Cal. 6643 - 857

The Seiko 6643-857 represents an important milestone in Seiko's 1999 lineup. Powered by the 6643 caliber with 35j jewels beating at 21,600 bph, it delivers a 55 hours power reserve. [seikata-wm-2f69e1b418d5]

Also known as: Helmet, Emperor

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

40mm

Case Thickness

12.0mm

Lug Width

20mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

50m

Dial Color

Navy

Jewels

35j

Frequency

21,600 bph

Power Reserve

55 hours

Year

1999

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