The compact ESW-T4107/925ML21 Desk Stand transmitter with microphone is an optional component for use with Audio-Technica's Engineered Sound Wireless systems (sold separately). The transmitter comes with a 21" MicroLine ES925 gooseneck microphone that delivers clear, present dialog capture with a moderate level of surrounding noise rejection. There's a two-state LED mute status indicator light on the top panel with seven selectable custom colors for at-a-glance verification. The transmitter supports use while charging via USB for always-on availability. ESW systems (sold separately) employ DECT automatic frequency management technology, so there's no channel programming necessary. Remove the transmitter from the charger (sold separately), and it's ready to deliver interference-free wireless audio performance.