Seiko Cal. 6631 - 765

The Seiko 6631-765 represents an important milestone in Seiko's 1977 lineup. With its 21mm lug width and 13.0mm profile, it sits comfortably on most wrists. [seikata-wm-9d18fee47bbf]

Also known as: Sportsmatic

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

46mm

Case Thickness

13.0mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

50m

Dial Color

Green

Jewels

30j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1977

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