Seiko Cal. 5638 - 828

The 5638-828 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 5638 caliber with 18j jewels beating at 28,800 bph, it delivers a 41 hours power reserve. [seikata-wm-b7425cc20ccc]

Also known as: UFO

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

10.8mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

40m

Dial Color

Blue Sunburst

Jewels

18j

Frequency

28,800 bph

Power Reserve

41 hours

Year

1968

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