Connect to your landline for standard conferencing. Connect to a PC / Mac via USB for VoIP functionality. PSTN direct dial, redial, rapid dial, recall, second flash. Make Skype conference calls using your PC / Mac. Using the 3.5 mm headset jack in your iOS or Android phone or tablet & even your cell phone can become a robust conference phone. Caller ID / Type: Base; Speakerphone: Base; Volume Control: Speakerphone; Conferencing: 3-Way.