Seiko Cal. 6638 - 400

The Seiko 6638-400 represents an important milestone in Seiko's 1992 lineup. With its 18mm lug width and 14.8mm profile, it sits comfortably on most wrists. [seikata-wm-7db5ec21b63e]

Also known as: Bullhead

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

41mm

Case Thickness

14.8mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

180m

Dial Color

Cream

Jewels

26j

Frequency

36,000 bph

Power Reserve

37 hours

Year

1992

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