Features: Rated operating voltage: DC12V-24V Working Voltage limits: 9-26V USB Output: 5V/2.1A Working Temp: 0-50 Support Play format: MP3 BT Version: Version 3.0+EDR Bluetooth sound processing: A2DP(Advance Audio Distribution Profile) Bluetooth transmission distance: 10M Bluetooth microphone effective range: 0.5-2M FM transmission frequency: 87.5-108Mhz Product includes 1 x Bluetooth Car MP3 Player(No Retail Box) 1 x User Manual