Seiko Cal. 6635 - 721

The Seiko 6635-721 represents an important milestone in Seiko's 1970 lineup. With its 21mm lug width and 8.8mm profile, it sits comfortably on most wrists. [seikata-wm-ed86c934b74c]

Also known as: Bellmatic

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

8.8mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

180m

Dial Color

Champagne

Jewels

26j

Frequency

21,600 bph

Power Reserve

45 hours

Year

1970

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