1. TF card expansion: 32G max (not included) 2. Output power: 3W 3. Battery voltage: 3.7V 4. Charging voltage: 5V 5. Standby time: 4-5 hours 6. Signal to noise ratio: 80dB 7. FM transmission frequency: 87.6-108MHz 8. Power source: battery 9. Charging time: 2-3 hours 10. Duration: 2-3 hours 11. Battery capacity: 800mAh 12. Battery type: Lithium-ion battery BL-5C 13. Compatible with: mobile phone, PC, MP4, MP3, MP5, PSP, TF/Micro SD card 14. Support: FM, TF music player, SD card music player 15. Function: AUX function, song 16. Connection method: wireless, wired 17. Interface: TF card slot, SD card slot, 3.5mm audio feature: - Can play MP3 music from TF/SD/MMC; - FM radio can automatically scan and remember channels; - With the audio cable jack, you can easily connect to your computer, MP3, MP4, mobile phone, etc. - Standard 3.5mm headphone jack for listening to radio and music on headphones; - Select radio channels and MP3 music, buttons from 0 to 9; - In MP3 mode, when the power is off, it can be played on the next boot; - With the BL-5C rechargeable lithium battery, you can connect via USB, connect the data cable to a computer or a USB power adapter, or use a charger, etc. to charge it.