At home or in the office, the PC 21-II headset has been specially designed for easy Internet-based phoning. Its single-sided wearing style lets you enjoy the conversation while being in touch with what's going on around you. And the lightweight, adjustable headband is comfortable to wear all day long. So you can be sure that you are clearly heard, the PC 21-II has an improved noise canceling microphone. It reduces background noise, to give you great voice quality, and is highly sensitive too, making it perfect for when you want to use speech recognition applications. Just adjust its flexible boom arm. Move it up/down or forward/back to position it where it needs to be.