Audio-Technica ESW-T4107 ESW Desk Stand TransmitterThe compact ESW T4107 Desk Stand transmitter is an optional component for use with Audio Technica's Engineered Sound Wireless systems (sold separately). The transmitter is compatible with over fifteen Audio Technica gooseneck microphones (sold separately) available in cardioid, hypercardioid, or MicroLine 90 cardioid patterns allowing you to tailor the system to multiple applications. There's a two state LED mute status indicator light on the top