The MXL AC-400 is a personal USB web conferencing microphone. The AC-400 facilitates clear, intelligible communication over the Internet from a desktop or laptop computer in any workspace. Because it is a personal mic, the AC-400 records only the speaker and not surrounding sounds. With the outstanding voice clarity, it will sound almost as if you are speaking face-to-face with someone in another building, another state, or another country. Use the AC-400 with web conferencing software, voice recognition software and dictation software. The durable, all-metal construction of this microphone makes it suitable for any office environment. The AC-400 features a headphone jack and a mute button. The MXL AC400 works well by itself or it can be used with up to three optional AC-40EXT mics to include more people in the conversation.