CQtransceiver Comfortable Landline Wired Telephone Headset RJ9 Connector for Plantronics Phone T10 T20 T50 T100 T110 Direct connect over the head headset, no additional amplifiers or adapters required 2M coiled wire Flexible boom design allows to adjust mic freely RJ9 connector to replace telephone handset Monaural over-the-head wearing style for comfort and awareness of environment