Analog Port Handsfree Unit Provides Electra Elite Multiline Terminals with the ability to interface with an analog device such as a cordless telephone, facsimile machine, external speakerphone, NEC's VoicePoint, Automatic Dialer, or modem. Incoming calls ring on devices installed to the APR-U unit. Each terminal with an APR-U unit installed requires power from an ACA-U unit.