Seiko Cal. 6638 - 424

The Seiko 6638-424 represents an important milestone in Seiko's 1967 lineup. Powered by the 6638 caliber with 34j jewels beating at 21,600 bph, it delivers a 60 hours power reserve. [seikata-wm-448b561dcb09]

Also known as: Bullhead

Specifications

Movement

Automatic

Case Material

PVD Black

Case Width

41mm

Case Thickness

13.9mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

170m

Dial Color

White

Jewels

34j

Frequency

21,600 bph

Power Reserve

60 hours

Year

1967

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