Wantek Wired Call Center Telephone Headset RJ9 Headphone with Mic for NEC Aspire DT300 DSX Polycom 335 400 Avaya 1416 Aastra 6757i Mitel 5330 ShoreTel IP230 IP Phones(H210P01A) Only works for some specific phones with Standard Modular RJ9 Headset Port. SEE COMPATIBLE PHONE LIST IN DESCRIPTION, BUY THE ITEM ONLY IF YOU HAVE ONE OF THE PHONE MODELS LISTED BELOW. Direct connect headband telephone headset headphone, No additional amplifiers or adapters required. Superior Call Center quality sound headset with flexible adjustable noise canceling microphone. Super Lightweight, Super Durable Headset with Comfortable ear and mic cushions for all day use. Shirt clip included. NO Mic Mute & Volume Control built in.