Seiko Cal. 5640 - 961

The 5640-961 is a sought-after Kinetic piece from Seiko's golden era. Powered by the 5640 caliber with 21j jewels beating at 28,800 bph, it delivers a 45 hours power reserve. [seikata-wm-022f1b57e9be]

Also known as: Tuna, Crown

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

11.3mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

150m

Dial Color

Green

Jewels

21j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1966

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