Seiko Cal. 6643 - 535

The Seiko 6643-535 represents an important milestone in Seiko's 1980 lineup. Powered by the 6643 caliber with 29j jewels beating at 28,800 bph, it delivers a 45 hours power reserve. [seikata-wm-d9f070ada7e5]

Also known as: Helmet

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

44mm

Case Thickness

12.8mm

Lug Width

19mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

30m

Dial Color

Navy

Jewels

29j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1980

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