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
Authentication Notes
Bracelet
LowProbable
The lugless case constrains the bracelet absolutely
There are no conventional lugs, so the watch takes a purpose-made bracelet and end-piece and cannot accept a standard strap without an adapter. A UFO presented on a generic strap has lost its original bracelet — very common, and a value rather than authenticity question, but the case ends should be inspected for the damage that forcing a non-original fitting causes.
Inspection points
No inspection checklist has been published for this reference.