Seiko Cal. 6640 - 743

The Seiko 6640-743 represents an important milestone in Seiko's 1998 lineup. Powered by the 6640 caliber with 24j jewels beating at 28,800 bph, it delivers a 56 hours power reserve. [seikata-wm-593007a7353f]

Also known as: Tuna, Navigator

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

38mm

Case Thickness

14.7mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

60m

Dial Color

Black

Jewels

24j

Frequency

28,800 bph

Power Reserve

56 hours

Year

1998

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