Callez Corded Headset Headphones Ear Phone with Quick Disconnect for Networks Nt Nothern PBX Norstar M7208 M7310 Polycom NEC Electra Elite DTU DPT Series E Mitel Rolm Voip IP Telephone(H300QDRJ1E) Superior quality sound with the flexible adjustable noise cancellation microphone. Direct connect over-the-head headset headphone, No additional amplifiers or adapters required. NO Mute / Volume Control built in. Comfortable ear and mic cushions, Most easy setup headset solution, Super Durable,Super Lightweight ONLY PURCHASE IF YOU HAVE ONE OF THE PHONE MODELS LISTED BELOW IN DESCRIPTION, CHECK OUR STORE FOR HEADSETS FOR OTHER PHONE MODELS OR CONTACT US FOR COMPATIBILITY GUIDE!