Andrea Electronics C1-1020700-1 model PCTI - 3 Way Personal Computer Telephone Interface - Andrea Electronics" audio accesories are designed with the needs of our customers in mind. Enhancing the audio experience for our customers is the goal. 3-way switching of an Andrea headset to a PC, a phone, or both. Enabling headset users to connect to their PCs and their telephones simultaneously to allow voice-enabled computing and telecommunications functions easily and efficiently. Connects an Andrea PC headset to most telephones (both single line and digital PBX) and to a PC. 3-way conferencing in position allows person on headset, person on phone, and person VoIP through computer all to communicate simultaneously. Use the headset while on the phone instead of the phone handset. Use the headset with the PC for speech recognition, VoIP, or any PC audio output. Single control point for flexible connections without plugging and unplugging cables, including: Select handset or headset, Adjust headset speaker volume, Mute headset microphone, Control Computer Speakers (On / Off), Select PC, Phone or Both