Seiko Cal. 6640 - 984

The 6640-984 is a sought-after Spring Drive piece from Seiko's golden era. With its 18mm lug width and 14.5mm profile, it sits comfortably on most wrists. [seikata-wm-5a1af6cf38f0]

Also known as: Shogun, Bullhead

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

37mm

Case Thickness

14.5mm

Lug Width

18mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

120m

Dial Color

Navy

Jewels

31j

Frequency

21,600 bph

Power Reserve

51 hours

Year

1987

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