Seiko Cal. 6660 - 644

Released in 1974, the Cal. 6660 with design code 644 was part of Seiko's domestic market collection. Powered by the 6660 caliber with 30j jewels beating at 21,600 bph, it delivers a 38 hours power reserve. [seikata-wm-fce20960ae7f]

Also known as: UFO

Specifications

Movement

Quartz

Case Material

Gold-Plated

Case Width

42mm

Case Thickness

12.3mm

Lug Width

18mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

120m

Dial Color

Silver

Jewels

30j

Frequency

21,600 bph

Power Reserve

38 hours

Year

1974

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