Seiko Cal. 6638 - 257

The Seiko 6638-257 represents an important milestone in Seiko's 1986 lineup. Powered by the 6638 caliber with 28j jewels beating at 21,600 bph, it delivers a 68 hours power reserve. [seikata-wm-2b9265649b84]

Also known as: UFO, Goldfeather

Specifications

Movement

Quartz

Case Material

Stainless Steel

Case Width

36mm

Case Thickness

8.6mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

190m

Dial Color

Cream

Jewels

28j

Frequency

21,600 bph

Power Reserve

68 hours

Year

1986

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