Audio-Technica ATW-T3201 Wireless Bodypack Transmitter | Frequency: DE2 (470 to 530 MHz)For true mobility and hands free use, the ATW T3201 bodypack transmitter is a great choice. Durable metal body keeps the transmitter protected from rough handling. Transmitter is powered with 2 AA batteries (not included). Depending on the batteries in use, the transmitter typically runs for 8 9. 5 hours of continuous use. With Audio Technicas 3000 Series you can mix and match components to create the wireless system that works best for you. Options