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Dial

6309 service replacement dial

Probable

Seiko supplied replacement dials for the 6309 through its service network long after the reference was discontinued, and after tritium had been withdrawn. A service dial is therefore typically found with modern luminous compound in a watch whose hands still carry aged tritium — a glow mismatch that is easy to see in the dark and easy to miss in daylight.

Part reference

Brand
Seiko
Identifying marks
Modern lume that fluoresces strongly and evenly; later printing conventions; frequently no factory mark where the original dial carried one.

Supplied only through the service network — finding this part fitted is a service observation, not a finding against the watch.

Documented variations

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.

  • Seiko service dial

    ServiceProbable

    Whole production

    Genuine Seiko part fitted by an authorised service centre. Affects originality and therefore value; it is not an authenticity finding and the watch is not a composite because of it.

  • Aftermarket reproduction dial

    AftermarketProbable

    Whole production

    Third-party dials made to resemble the original, sold openly for restoration. Distinguished from a service dial by print quality, marker seating and the absence of Seiko's own part numbering on the reverse. Where an aftermarket dial is presented as original, the misrepresentation is the finding — not the part.

Documented on these references

  • Seiko 6309-7040Service

    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.

Provenance of this record

Sources & Evidence

Primary sourceTechnical documentation

Seiko caliber technical guides and parts catalogues

Seiko Watch Corporation / Seiko Instruments

Accessed
2026-08-18

Cited for

This referenceProbable
Community sourceCommunity knowledge

The Watch Site — Seiko reference and dial-code discussion

The Watch Site

Accessed
2026-08-18

Cited for

This referenceProbable
View source ↗

Last verified: Not yet reviewed