Specifications:Color: BlackSize: The length of this item: 26cmThe audio cable length: 30cmRated working voltage: 12V- 24VLimit working voltage: 8V-36VConsumed power: 0.5WWorking voltage: -20-50Support format: MP3?WMASNR(Signal to Noise Ratio) ?60dBDistortion: 0.1Reception frequency: 20Hz-15 KHzFM transmission frequency: 87.5-107.0MHzUSB charging output: 5V/500mABluetooth Version: Blue 2.1 + EDRBluetooth transmission distance: 10 - 15mBluetooth sound processing: with the AD2P function (Advance Audio Distortion Profile)How to use it:Inserting the plug of the cigarette lighter into the hole of the car cigarette lighterTurn on the Car Radio、 and utilize the FM of the Radio to search a vacant channel、 for example、 88.1 Hz、 or slightly adjust the FM channel、 you can also adjust the frequency in accordance with the frequency of Car RadioInserting the external USB flash disk、 or SD/MMC card into this item、 it will play the music in the USB flash disk、 or SD/MMC card.Compatible : Bluetooth-enabled mobile devices、 Smartphone、 Tablet PC、 etc.Features:100% Brand New and High QualityOne button for answer and hung up、 easy operation and convenient to use、 it can avoid the potential safety hazard of answer calls during driving.No need any equipments in the car、 you can easily pair the Bluetooth mobile phone and adjust the frequency of music.Play music of phone、 external USB flash disk and SD card; Support the MP3/WMA music formatUse the DSP (digital signal processing) echo cancellation technology and noise suppression (CVC) technology to create an excellent voice qualitysupports A2DP playback and hands-free callSupport two cell phone connection Bluetooth、the power supply after opening、automatic back to even、automatic into the matching condition.Directly powered by the car cigarette lighter、 no need the external power supplyCan charge for various smart phones (USB out port: 5V/500mA)Broadcast stored music by the automobile through car stereo system