Audio-Technica PRO 88W-R35 VHF Wireless Lavalier System with ATR35 Mini Omnidirectional Clip-On Microphone Provides freedom of movement for video production, computer applications and business presentations Features two switchable frequencies for interference-free operation and high-band VHF operation for superior sound Normal operating range from 100' up to 300' under optimum conditions, and the durable, flexible antenna can be positioned for best reception Real-time monitoring capability with included earphone Rugged design and construction with handsome non-reflective finish and a quick and reliable mounting system for camcorder use Receiver and transmitter are each powered by a single 9V battery