Seiko Cal. 5640 - 550

The 5640-550 is a sought-after Solar piece from Seiko's golden era. Powered by the 5640 caliber with 32j jewels beating at 21,600 bph, it delivers a 65 hours power reserve. [seikata-wm-fc7d52a1cad8]

Also known as: Rally, Sportsmatic

Specifications

Movement

Solar

Case Material

Two-Tone

Case Width

39mm

Case Thickness

9.7mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

100m

Dial Color

Black

Jewels

32j

Frequency

21,600 bph

Power Reserve

65 hours

Year

1966

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