Seiko Cal. 6638 - 240

The Seiko 6638-240 represents an important milestone in Seiko's 1991 lineup. The Bidirectional bezel and 38mm case give it a distinctive presence on the wrist. [seikata-wm-8b667f08a929]

Also known as: Bullhead

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

38mm

Case Thickness

15.2mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

200m

Dial Color

Blue Sunburst

Jewels

26j

Frequency

21,600 bph

Power Reserve

51 hours

Year

1991

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