Seiko Cal. 6640 - 484

The 6640-484 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 6640 caliber with 36j jewels beating at 21,600 bph, it delivers a 50 hours power reserve. [seikata-wm-4b3dcaaa0eab]

Also known as: Tuna, Bullhead

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

9.6mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

100m

Dial Color

Silver

Jewels

36j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1990

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