Features: Support for hands-free telephone，convenient and safe on the phone. With multi-function remote control，Can realize number song selection and choose frequency. Support multipoint connections: can connect two phones at the same time. Built-in FM transmitter Support USB disk and Micro SD card， support TF card Excellent voice quality， use the DSP (digital signal process) technology to echo cancellation With 3.5 mm line-in jack， support external audio devices Switch to hands-free mode automatically from music playing status when receives an incoming call Dual USB charging ports for charging for iPod for iPhone， for Samsung， for iPad， for Nokia and other mobile devices(Output 5V/2.1A) Support 12-24V voltage from the car cigarette lighter Description: Size: 8.0 x 7.0 x 3.2cm Package weight: 2.1 oz/61g The audio cable length: 70cm Frequency range: 87.5-108.0Mhz Output Frequency: 20Hz-15KHz Supply voltage: 12-24V Rated current: 90mA Power consumption: 1W Work temperature: 0-50 degrees Support file format: MP3/WMA USB Charge output: 5V/2.1A Music format: MP3 format USB Maximum support: 32G Micro SD Maximum support: 32G Bluetooth version 2.1 + EDR Transmit distance: 10m Operating system: Win XP/Win vista/Win7 SNR Greater or equal to 60dBHow to use it: 1.Using FM transmitter function: 1)Plug the FM transmitter into your vehicle’s cigarette or power port 2)Turn your radio to an unused FM frequency， then match the same frequency of this unit 3)Insert a USB flash drive or Micro SD card which containing MP3 files into USB port or memory card slot of this unit accordingly， it will play and transmit the MP3 files automatically 4)Line-in function for:Use the provided audio cable to connect an MP3/Mp4 players or another external device to the AUX input of this unit， when using this function， please playback of USB or memory card， and all functions will be controlled by the external device Package Included: 1 x MP3 Player FM Transmitter Hands-free Car Kit Charger 1 x Audio cable 1 X Remote controller