Shure QLXD14/153T S50, Digital UHF Wireless System with Pocket Transmitter and Earset Microphone, Frequency band S50: 823 - 832 MHz and 863 - 865 MHz, 24 bit / 48 kHz audio signal, AES-256 encryption for tap-proof transmission, Up to 72 MHz switching bandwidth, 22 compatible channels in an 8 MHz TV band,