The WIR RX22-4N is a four-channel selectable, infrared receiver compatible with transmitters operating on the 2.3/2.8/3.3/3.8 MHz bandwidth. Dual infrared detectors maximize sensitivity and operating range. Range of up to 30,000 square feet (2,800 square meters) in single-channel mode when used with a Williams Sound WIR TX925 or WIRTX90 infrared system. Comfortable, body-pack design features convenient channel selector and easy-to-use on/off volume control. The RX22-4N can be used with mono or stereo headphones, earphones or a neckloop (lanyard included).