Seiko Cal. 6638 - 725

The 6638-725 is a sought-after Automatic piece from Seiko's golden era. Powered by the 6638 caliber with 26j jewels beating at 21,600 bph, it delivers a 71 hours power reserve. [seikata-wm-f6ba62949def]

Also known as: Bullhead, Helmet

Specifications

Movement

Automatic

Case Material

Stainless Steel

Case Width

34mm

Case Thickness

8.4mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

50m

Dial Color

Silver

Jewels

26j

Frequency

21,600 bph

Power Reserve

71 hours

Year

1966

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