Seiko Cal. 5638 - 640

The 5638-640 is a sought-after Quartz piece from Seiko's golden era. With its 20mm lug width and 14.3mm profile, it sits comfortably on most wrists. [seikata-wm-e28bc20695ec]

Also known as: Sportsmatic

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

14.3mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

70m

Dial Color

Navy

Jewels

35j

Frequency

21,600 bph

Power Reserve

70 hours

Year

1991

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