Wireless handheld microphone with built-in transmitter offers 96 UHF channels so your presentation will go smoothly. All wireless devices of any type are subject to interference caused whenever a receiver can "hear" more than one transmitter broadcasting on the same frequency. This "jamming" effect can sound like a howl or squeal distortion of the mic signal or even no sound at all coming from the receiver. UHF frequencies are less susceptible to environmental noise. This transmitter gives you 96 channels from which to choose with a frequency range from 514 MHz to 544 MHz. Use only with Amplivox Executive Sound Column, Presidential Plus or Elite lectern SW models.