3.5mm Car Bluetooth Music Reciever: This music receiver(hands-free) is designed to receive music from mobile phones  or transmitters that feature Bluetooth wireless technology.The music receiver can be used with almost any audio receiver with an audio input jack,including automobiles.Listen to music from your smart phone or mp3 player on your existing home or car audio system.To enjoy car music,call solutions,the use of smart phones to make calls and listen to music through the car stereo.The product is embedded echo cancellation microphone.Using only one button,you can easily switch between music and phone.