Seiko Cal. 5640 - 999

Released in 1988, the Cal. 5640 with design code 999 was part of Seiko's domestic market collection. With its 18mm lug width and 15.9mm profile, it sits comfortably on most wrists. [seikata-wm-748229ed56dd]

Also known as: Monster, Sportsmatic

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

44mm

Case Thickness

15.9mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Rotating

Water Resistance

60m

Dial Color

Cream

Jewels

24j

Frequency

36,000 bph

Power Reserve

58 hours

Year

1988

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