High quality Noise Canceling Call Center Headset Compatible with following Polycom phone models: Media Business Phone VVX101, VVX201, VVX300/310, VVX400/410, VVX500, VVX 600, SoundPoint IP 335, 450, 550, 650, 670, Microsoft Lync CX200, CX600. | This RJ9 headset also Works With other Telephone Models :Plantronics Nortel Shoretel Aastra Avaya Lucent Allworx AltiGen Comdial Digium Gigaset InterTel MiVoice etc.SEE MORE COMPATIBLE PHONE LIST IN DESCRIPTION. | HD Voice for Clear Communication: Wideband Sound telephone headset enables natural listening experience, noise canceling microphone provides greater focus and concentration by blocking background noise, features large volume control and mute button, provides extra convenience while conversations. | Noise-Canceling microphone| Flexible, Rotatable microphone boom, user may place the speaker on left or right ear anytime | Soft, leatherette ear cushion for all-day comfort | Click-Stop adjustable headband.| Durable, 2 Years Warranty Included! | EASY TO USE: Convenient inline Volume Switch & Mic Mute button for easy access, just one press the key to control your sound when talking. 5.3ft long cord offers flexibility to move around, designed to keep pace with the demands of work and life.