Seiko Cal. 6613 - 631

The Seiko 6613-631 represents an important milestone in Seiko's 1991 lineup. With its 19mm lug width and 15.2mm profile, it sits comfortably on most wrists. [seikata-wm-744994464b11]

Also known as: Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

15.2mm

Lug Width

19mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

180m

Dial Color

Silver

Jewels

30j

Frequency

36,000 bph

Power Reserve

38 hours

Year

1991

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