Storms approaching? Become aware of potential emergencies with the Medallion Series Weather Alert Transmitter. It works with any compatible weather alert radio and transmits a wireless signal to any Medallion Series Receiver when the NWS (National Weather Service) broadcasts a warning. Offering a simple, plug-in connection to the radio, the transmitter is powered by two AA batteries (included). Features million-code technology for interference-free performance in apartments, condominiums, dormitories, hotels and public housing; also ideal for use in single-family homes. FCC compliant.