Seiko Cal. 6638 - 425

The 6638-425 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 6638 caliber with 26j jewels beating at 21,600 bph, it delivers a 69 hours power reserve. [seikata-wm-ac71caee743f]

Also known as: Bullhead, Goldfeather

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

35mm

Case Thickness

10.2mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Cream

Jewels

26j

Frequency

21,600 bph

Power Reserve

69 hours

Year

1973

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