Seiko Cal. 3871 - 991

Released in 1969, the Cal. 3871 with design code 991 was part of Seiko's domestic market collection. With its 19mm lug width and 15.6mm profile, it sits comfortably on most wrists. [seikata-wm-7cfaaa6cccec]

Also known as: Helmet, World Timer

Specifications

Movement

Quartz

Case Material

Gold-Plated

Case Width

40mm

Case Thickness

15.6mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

90m

Dial Color

Green

Jewels

19j

Frequency

21,600 bph

Power Reserve

36 hours

Year

1969

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