Seiko Cal. 3820 - 640

The Seiko 3820-640 represents an important milestone in Seiko's 1973 lineup. With its 18mm lug width and 12.2mm profile, it sits comfortably on most wrists. [seikata-wm-70ec21ea63cd]

Also known as: Turtle, Navigator

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

12.2mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

70m

Dial Color

Green

Jewels

19j

Frequency

36,000 bph

Power Reserve

71 hours

Year

1973

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