Nady EO3RXCC EO3 In-Ear Monitor Wireless Receiver Powered by a 9V alkaline battery Operates on the special 72-76 MHz band, which will not interfere with VHF Transmitter range is up to 300 Power on/off switch, battery status LED, volume control and mute control Includes miniature earbuds with special soft rubber &#8220;custom-fit&#8221; inserts