Seiko Cal. 6640 - 443

The Seiko 6640-443 represents an important milestone in Seiko's 1969 lineup. Powered by the 6640 caliber with 31j jewels beating at 28,800 bph, it delivers a 52 hours power reserve. [seikata-wm-b0c03b9a25a3]

Also known as: Rally, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

38mm

Case Thickness

15.4mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

80m

Dial Color

White

Jewels

31j

Frequency

28,800 bph

Power Reserve

52 hours

Year

1969

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