Function:1. Play USB/TF card in the MP3 audio file2. External audio input3. Built-in battery4. External power charging interface5. FM auto scam radio6. LED digital display Technical Specification:1. Input DC-5V2. Built-in BL-5C battery3. Frequency response 150-18000HZ4. Power output RMS 3W=THD10%5. FM 87MHz-108MHz