Seiko Cal. 6640 - 827

The 6640-827 is a sought-after Spring Drive piece from Seiko's golden era. With its 21mm lug width and 13.8mm profile, it sits comfortably on most wrists. [seikata-wm-2c1169ad29ad]

Also known as: Bullhead

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

39mm

Case Thickness

13.8mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

150m

Dial Color

Silver

Jewels

24j

Frequency

36,000 bph

Power Reserve

57 hours

Year

1988

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