Shure BLX14/SM31 T11, Wireless System, SM Presenter Series, UHF wireless system with BLX1 pocket transmitter and SM31 headset microphone, Up to 3 systems simultaneously, Pilot tone, Microprocessor driven antennae diversity, Quick-Scan function for free frequency detection, Condenser SM31 microphone capsule with 45 - 20,000 Hz frequency range and cardioid characteristic, Plastic receiver, Integrated antennae, XLR and jack outputs, Audio status LEDs, Frequency range: T11 (863-865 MHz), Case included