Call Center Hands-free Headset Headphone Monaural Mic Mircrophone Noice Cancelling + Extra Cushions for Avaya Nortel Nt Yealink Ge Emerson Viop POE Nec Mitel Office Desktop Ip Telephone Phone Direct connect over the headset headset headphone. No additional amplifiers or adapters required. Superior quality sound with the flexible adjustable noise cancellation microphone. Most easy setup headset solution, Extra ear and mic cushions. Please see compatible model list below Shirt clips included. NO Mute / Volume Control built in. NOT for Cisco brand IP phones, please see compatible list below