Function & Connection: Support listening to music and answer phone calls.Support playing the music documents in SD card or USB， then FM transmitter to car audio through wireless system.Support using bluetooth to connect your phone， then FM transmitter to car audio through wireless system.Support using the 3.5 mm audio cable to connect your phone， then FM transmitter to car audio through wireless system. (You can also use 3.5 mm audio cable to connect this device to your car audio to play music or answer phone calls instead of using FM Transmission function.)Listening music via bluetooth and answering calls for almost all smartphones， sush as iPhone， Samsung， HTC， LG， etc.Product Features:1.33" LCD screen car MP3 playerSupports bluetooth speakerphoneAdopts call echo cancellation and noise suppression (CVC) technologyAutomatically switch from music player to call modeEquipped with stereo bluetooth and FM transmitter technologySupports USB flash drive， SD cardSupports external MP3 player audio inputSupports MP3 music format Supports automatic power-off memory function Compatible with remote controllerSpecifications:Compatible Brand: UniversalCompatible Product: Almost all smartphones， sush as iPhone， Samsung， HTC， LG， etcFeatures: FM Transmitter， Bluetooth Wireless， LCD ScreenFrequency Response: 20Hz-15KhzFM Transmitting Frequency: 87.5~108MhzSupported Format: MP3Rated Operating Voltage: 12VUltimate Operating Voltage: 9-26VSNR Ratio > 60dBLeft/Right Channel Separation > 60dBScreen Size: 1.33"Display Type: LCDBluetooth Version: 2.1Bluetooth Transmission Distance: 5 MetersSteps to use this MP3 bluetooth FM transmitter device to play music from your phone via bluetooth:1. Plug the device to the cigar lighter interface. (This device cannot store electric power， it must be plugged in your car's cigar lighter interface to get powered).2. Connect your phone to the device via bluetooth.3. Adjust the frequency of this device to be the same frequency as your radio.? (You can also use the 3.5mm audio cable to connect the device to your car radio/speaker instead， to play music.)Package Included:1 x FM Transmitter Bluetooth Car MP3 Player (USB flash disk， SD card， MMC are not included)1 x Remote Controller1 x 3.5 mm Audio Cable 1 x User Manual