Seiko Cal. 6668 - 556

Released in 1971, the Cal. 6668 with design code 556 was part of Seiko's domestic market collection. With its 19mm lug width and 8.8mm profile, it sits comfortably on most wrists. [seikata-wm-4de4286efc6b]

Also known as: Sumo, UFO

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

37mm

Case Thickness

8.8mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

50m

Dial Color

Navy

Jewels

31j

Frequency

21,600 bph

Power Reserve

52 hours

Year

1971

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