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Some specifications for this reference are on file; the record is incomplete.

Seiko · Vintage

Chronograph 6138

Ref. 6138-0011 — “UFO

discontinuedLugless 'Yachtsman' casePartially documentedLast reviewed Not yet reviewed

Missing informationCore fields not yet documented for this reference: Case diameter, Water resistance

Reference photography not yet on file

Seiko's own name for this case is 'Yachtsman'; 'UFO' is a collector nickname earned by the lugless case appearing to float on the wrist. Both names are in wide use and neither is wrong, but only one of them is Seiko's.

Some specifications for this reference require verification against manufacturer documentation.

At a glance

Brand
Seiko
Collection
Vintage
Reference
6138-0011
Production
1970–1979
Caliber
6138B
Case material
Stainless steel

Related references

Reference family timeline

Every generation in this lineage in production order. Spans are as documented; an open end means the reference is current or its end year is not established.

  1. 6138-0011UFO

    Chronograph 6138 · 6138B

    1970–1979This reference
  2. 6138-0030Bullhead

    Chronograph 6138 · 6138B

    1971–1978
  3. 6138-8020Panda

    Chronograph 6138 · 6138B

    1972–1978
  4. 6138-8039John Player Special

    Chronograph 6138 · 6138B

    1976–1979