Automatically release the line if the phone is not put down well or if it is off hook and the line is busy allowing a incoming callRinger with LED Visual LightGreen LED Lights and sound when phone is off hook (Handset is not on hook)Adjustable timer 15Minutes 30Minutes 60Minutes or unlimited MinutesLoud telephone ringer 95dbaAdjustable ringer switchAdjustable tone switchVery bright LEDWorks on PSTN / VOIP / Cable linesUses Regular RJ11 plugsA/C Adaptor SuppliedDesk and wall mountableConnects easily to telephoneFCC Approved