Seiko Cal. 3870 - 637

Released in 1982, the Cal. 3870 with design code 637 was part of Seiko's domestic market collection. With its 21mm lug width and 8.9mm profile, it sits comfortably on most wrists. [seikata-wm-bec7aba32a53]

Also known as: Helmet, Sea Horse

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

8.9mm

Lug Width

21mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

30m

Dial Color

Green

Jewels

28j

Frequency

28,800 bph

Power Reserve

37 hours

Year

1982

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