Seiko Cal. 5638 - 728

The 5638-728 is a sought-after Solar piece from Seiko's golden era. With its 22mm lug width and 15.9mm profile, it sits comfortably on most wrists. [seikata-wm-ea208eaa3e68]

Also known as: UFO

Specifications

Movement

Solar

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

15.9mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Blue Sunburst

Jewels

30j

Frequency

36,000 bph

Power Reserve

45 hours

Year

1976

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