Product Detail Sturdy metal housing (transmitter and receiver) 42 MHz bandwidth: 1680 tunable UHF frequencies for interference-free reception Enhanced frequency bank system with up to 12 compatible frequencies Adaptive-diversity reception for high reception quality Pilot tone squelch for eliminating RF interference when transmitter is turned off . The "Sennheiser ew 122-p G3 Cardioid Lavalier Wireless System, CH A" is best product for you. We recommended Sennheiser ew 122-p G3 Cardioid Lavalier Wireless System, CH A