Seiko Cal. 6640 - 505

The Seiko 6640-505 represents an important milestone in Seiko's 1970 lineup. With its 18mm lug width and 11.8mm profile, it sits comfortably on most wrists. [seikata-wm-3f7d364b04f2]

Also known as: Bellmatic

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

45mm

Case Thickness

11.8mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

60m

Dial Color

Black

Jewels

30j

Frequency

36,000 bph

Power Reserve

55 hours

Year

1970

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