Seiko Cal. 6640 - 644

The Seiko 6640-644 represents an important milestone in Seiko's 1985 lineup. With its 19mm lug width and 11.4mm profile, it sits comfortably on most wrists. [seikata-wm-8b75f2248cb1]

Also known as: UFO

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

41mm

Case Thickness

11.4mm

Lug Width

19mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

140m

Dial Color

Champagne

Jewels

17j

Frequency

28,800 bph

Power Reserve

61 hours

Year

1985

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