Add Plantronics sound quality and features to operator console, PBX or ADC systems. Easy to install and use, simply plug the adapter into the operator console, then plug in your Plantronics H-series headsets. Durable and portable unit delivers improved sound with a volume equalizer to maintain user listening preferences whatever the quality of incoming calls. Quick Disconnect feature lets user walk away from the phone without removing the headset or losing the call. Features: N/A; Connecting Types: N/A; For Use With: Most Telephone Systems; Accessory Type: N/A.