Dell B3465dnf Mono Laser Multifunction Printer - Manual (Page 109)

If the wall jack or equipment in your facility is not compatible with this type of connection, then you need to use a
telephone adapter. An adapter for your country or region may not come with your printer, and you may need to
purchase it separately.
There may be an adapter plug installed in the port of the printer. If you are using a telephone adapter or a facility
that has a cascaded or serial wiring scheme, then do not remove the adapter plug from the port of the printer.
Faxing 109