Seiko Cal. 6664 - 721

Released in 1975, the Cal. 6664 with design code 721 was part of Seiko's domestic market collection. Powered by the 6664 caliber with 36j jewels beating at 36,000 bph, it delivers a 59 hours power reserve. [seikata-wm-53bfbd569fc4]

Also known as: Helmet, UFO

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

42mm

Case Thickness

10.1mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Fixed

Water Resistance

90m

Dial Color

Green

Jewels

36j

Frequency

36,000 bph

Power Reserve

59 hours

Year

1975

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