Seiko Cal. 4590 - 640

The Seiko 4590-640 represents an important milestone in Seiko's 1968 lineup. Powered by the 4590 caliber with 28j jewels beating at 21,600 bph, it delivers a 48 hours power reserve. [seikata-wm-caa5efdbaa58]

Also known as: Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

46mm

Case Thickness

10.1mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Silver

Jewels

28j

Frequency

21,600 bph

Power Reserve

48 hours

Year

1968

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