Seiko Cal. 6640 - 813

The Seiko 6640-813 represents an important milestone in Seiko's 1976 lineup. With its 22mm lug width and 14.4mm profile, it sits comfortably on most wrists. [seikata-wm-2adb921a73d8]

Also known as: UFO

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

35mm

Case Thickness

14.4mm

Lug Width

22mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

70m

Dial Color

Green

Jewels

35j

Frequency

28,800 bph

Power Reserve

44 hours

Year

1976

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