Seiko Cal. 6684 - 640

This Hand-Winding model from 1968 features a 40mm Hardlex-Coated Steel case. With its 19mm lug width and 15.7mm profile, it sits comfortably on most wrists. [seikata-wm-e50e317ea657]

Also known as: Crown, Emperor

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

15.7mm

Lug Width

19mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

120m

Dial Color

Navy

Jewels

33j

Frequency

28,800 bph

Power Reserve

56 hours

Year

1968

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