Send sound from any device you choose such as a mobile phone, laptop, TV, smart speaker, instruments (such as guitars), microphones, or any device with a 3.5mm jack or RCA connection, to any nearby radio or stereo system using FM Radio waves. Broadcast your favorite music, radio show, audio, or voice to any FM radio receiver in your home, office, or car. | Can also be used for church services, meetings, small concerts, or mini drive-in movies with neighbors and at gyms. Often used in correctional facilities as well. | Thumbwheel that allows you to adjust the input for perfect audio quality and a two-level LED indicator to help set optimal signal level. It broadcasts clean, very high-fidelity stereo audio. | FCC compliant. Maximum distance is about 45 feet line of sight with no obstructions. Broadcast distance will vary depending on location. Frequency Range 87.5 MHz and 108 MHz. | AC adapter included, or 2 AA batteries (not included). Weight: 5.8 oz. Size 3" W x 3.5" H x 1" D. 1-year limited warranty. U.S. based tech support.