Seiko Cal. 6638 - 422

The Seiko 6638-422 represents an important milestone in Seiko's 1969 lineup. With its 21mm lug width and 12.7mm profile, it sits comfortably on most wrists. [seikata-wm-13bcb6d91689]

Also known as: Bullhead

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

42mm

Case Thickness

12.7mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

190m

Dial Color

Silver

Jewels

20j

Frequency

36,000 bph

Power Reserve

53 hours

Year

1969

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