Using this Shure SLX14 wireless belt pack system is easy. First, you'll need to get a separate power supply since it's not included. Once you have power, turn on the system and make sure it's set to the J3 band frequency range (572 - 596 MHz). Before using it, always double - check your country's wireless frequency laws to avoid any legal issues. When it comes to maintenance, keep the belt pack clean and dry. Avoid exposing it to extreme temperatures or moisture. Since the button on the belt pack is missing, be extra careful when handling it to prevent further damage. If you encounter any problems during use, it's best to contact Shure customer service for assistance.