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

Seiko · Prospex

Turtle

Ref. 6309-7040

discontinuedExport cushion diverPartially documentedEvidenceProbableLast reviewed Not yet reviewed
Lineage6309-7040SRP777 →Compare with next

Known Variants

Classification

FactoryDocumented as shipped from the factory for this reference and period.PeriodNot original to this watch, but correct for its production period.ServiceFitted by the manufacturer's own service network. Not a defect.AftermarketThird-party part. Affects originality, not authenticity.ModifiedGenuine parts in a configuration the factory did not sell. Affects originality and value, not authenticity.CounterfeitDeceptive reproduction intended to pass as genuine.UnknownEvidence on file does not settle the question.

Dial

Factory

Suwa-marked dial

Earlier dials carry the Suwa factory mark near 6 o'clock. Factory marks were dropped over the production life, so a late example without one is not missing anything.

Probable

Bezel insert

Aftermarket

Aftermarket replacement insert

Replacement inserts for this case are made in very large numbers and are among the most commonly fitted parts on any vintage Seiko. Expect one; note it, and do not weigh it as an authenticity signal on its own.

High confidence

Component compatibility

What this reference is documented to have carried, and in what capacity. A service part is the manufacturer's own work; only a counterfeit classification is a finding against the watch.

Documented calibers

  • Seiko 6309AFactoryDefault configurationHigh confidence

    1976–1988

Components

  • Bezel insert6309-7040 bezel insertFactoryDefault configurationProbable

    1976–1988

    Factory insert for the export Turtle.

  • Hands6309 diver handsetFactoryDefault configurationProbable

    Whole production

  • Crown6309 screw-down crown at 4 o'clockFactoryDefault configurationProbable

    Whole production

  • Dial6309 service replacement dialServiceProbable

    1988 →

    Supplied through the service network after production ended. The window records when the part was AVAILABLE FOR SERVICE, not when the watch was built — a serviced 1978 watch legitimately carries a 1990s service dial.