The Azden WLX-PRO+i VHF Wireless Lavalier Microphone System transforms your handheld smartphone or tablet into a wireless recording device. It includes a WLT/PRO VHF bodypack transmitter and WR-PRO VHF receiver. Firstly, the bodypack transmitter comes with an EX-503 lavalier microphone having an omnidirectional polar pattern. The transmitter allows you to switch between 2 VHF channels with a frequency of 169.445 MHz and 170.245 MHz. As for the WR-PRO VHF receiver, it provides a working distance of 250 feet. All the PRO series transmitters operate on the same of 169.445 MHz and 170.245 MHz, allowing you to interchange or add other PRO series units in the sound setup. Both the transmitter and receiver operate on a single 9V battery. Along with these two units, you get a 1/8" mono to stereo output cable, shoe mount, mounting strips, and belt clip.