Seiko Cal. 3813 - 631

The Seiko 3813-631 represents an important milestone in Seiko's 1989 lineup. With its 20mm lug width and 15.0mm profile, it sits comfortably on most wrists. [seikata-wm-da172f7f8f2d]

Also known as: UFO, Goldfeather

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

41mm

Case Thickness

15.0mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

80m

Dial Color

Black

Jewels

34j

Frequency

21,600 bph

Power Reserve

44 hours

Year

1989

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