Audio-Technica PRO 88W Wireless Cardioid Clip-on Microphone System (W88-57-829) Provides freedom of movement for video production, computer applications and business presentations Two switchable frequencies for interference-free operation High-band VHF operation for superior sound Normal operating range 100'; up to 300' under optimum conditions Durable, flexible antenna can be positioned for best reception Includes AT829mW miniature cardioid clip-on microphone