Extension ports can be configured to accommodate Plexus key telephones, standard analog telephones (including cordless), fax machines, answering machines, modems, Plexus door phones, Plexus operator consoles, credit card scanners, and 3rd party voice mail systems. No adapters are needed.

Analog Combination Interface (ACI) Micro-Plexus only- 4 trunks and 8 extensions

Analog Trunk Interface (ATI) 4 or 8 trunks

Analog Extension Interface (AEI) 8 extensions

Direct Inward Dial (DID) Analog Trunk Interface Card 4 DID trunks - Direct Inward Dialing (DID) is service offered by telephone companies in which the last digits (typically two to four) dialed by the caller are forwarded to the system on a DID trunk. DID allows the system to have several inbound dialed numbers that route directly to different users, user groups, auto attendants, fax machines, etc. DID also allows the system to have more telephone numbers than it has trunks because not all telephone numbers will be in use at the same time.