This Audio-Technica ATW-901 system includes an ATW-T901 bodypack transmitter and an ATW-R900 wireless receiver. But it doesn't come with a power supply. It operates in the 169.505 - 171.905 MHz frequency range. Before buying, make sure to check your country's wireless frequency laws as some frequency ranges may be illegal in certain countries.

Using this Audio - Technica ATW - 901 system is easy. First, connect the ATW - T901 bodypack transmitter to your audio source. Then, pair it with the ATW - R900 wireless receiver. Remember, you'll need to provide your own power supply. When using, keep the transmitter and receiver within a reasonable distance for a stable connection. As for maintenance, keep them clean and dry. Avoid exposing them to extreme temperatures. Also, always check your country's wireless frequency laws before using it to avoid any legal issues.