External Wireless Lapel & Headset Mic Kit for any Sound System! Also provides a 2nd wireless channel for all AmpliVox "SW" model lecterns and sound systems. Hands Free. Freedom to Roam! Unlike many other VHF systems on the market the S1600 has two switch selectable radio channels to choose from. Ideal for LCD projectors computer presentations slide shows or presentations using visual aids. Allows you to freely roam the speaker's platform into the audience or anywhere up to 300 feet away. Includes lapel mic. headset mic, transmitter, receiver. 2 frequency groups available (171.105 / 171.845 or 169.505 / 170.305). Requires two 9-volt batteries (not included). Features: -Lapel mic and hedset mic plus receiver and transmitter. -2 frequency groups available (171.105 / 171.845 or 169.505 / 170.305). -6 Year Warranty.