Seiko Cal. 6640 - 521

This Hand-Winding model from 1975 features a 35mm PVD Black case. With its 18mm lug width and 14.3mm profile, it sits comfortably on most wrists. [seikata-wm-e827195faf9c]

Also known as: Tuna

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

35mm

Case Thickness

14.3mm

Lug Width

18mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

110m

Dial Color

Champagne

Jewels

32j

Frequency

36,000 bph

Power Reserve

65 hours

Year

1975

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