Specifications:Hands-free bluetooth-compatible support / hang up / reject / redial, safer driving.Audio receiver: transmit music from the phone, TF card (Micro SD card) to the car stereo, speaker, headphones, very powerful.Built-in echo cancellation microphone, pure sound output.Automatic connection to the latest matching device, convenient for couple.USB cable for power supply, easy to charge.Support TF card playback function, easy to operate.Item Name: bluetooth-compatible Audio ReceiverBluetooth Version: V3.0 EDRTransmission Distance: 10mSupport bluetooth-compatible hands-free calling function.Support bluetooth-compatible A2DP stereo.Frequency: 2.4GHzWorking Time: up to 5 HoursSize: 5.5cm x 2.5cm x 1.28cm/2.17" x 0.98" x 0.50" (Approx.)Notes:Due to the light and screen setting difference, the item& 39;s color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x bluetooth-compatible Audio Receiver1 x USB Cable1 x User Manual