Audio-Technica ATW-3131BC 3000 Series Wireless Lavalier System 996 - 1001 UHF frequencies C Band Frequency: 541.500 MHZ to 566.375 MHz Nine pre-coordinated frequency scan groups simplify selection of usable frequencies in a multi-channel wireless system True Diversity operation reduces dropouts Advanced digital Tone Lock squelch effectively blocks stray RF and communicates transmitter data for receiver display Includes ATW-R3100b receiver and ATW-T310b UniPak transmitter with AT831cW lavalier microphone