1、Wireless bluetooth FM transmitter adapter for car radio, to transmit calls,MP3 music,mobile phone voice to car speakers. 2、Compatible with for iOS Tablet, for iPhone, for Samsung, for Google, for LG, for HTC and Bluetooth devices. 3、Built in microphone, automatically switch to hands free mode when answering a call. One click answer,reject,raise hand,recall. 4、The voltage is displayed for 3 seconds when plugged into the car socket. Always keep the battery healthy. Then it goes to auto play mode. 5、Support Bluetooth , U disk , memory card , MP3 , wma player. With anti interference performance and CVC technology. 6、Listen to music while charging. Automatic connection and memory pairing after power on. 1 x Adapter Item Type:  Car Mp3 Bluetooth AdapterModel: A9Colour: BlackMaterial: ABSFunction: Bluetooth Adaptation, FM TransmissionScope of Application: Car1: Bluetooth Hands Free Call; 2: Echoes Cancellation and Noise Processing During a Call; 3: Stereo Bluetooth and FM Transmission Technology; 4: Support USB , Memory Card (Not Included) , Bluetooth Connection; 5: Support MP3 Format Music; 6: Automatic Power Off Memory Function; 7: Cigarette Lighter Power Supply: DC12V-24V Voltage Power Supply; 8: Bluetooth Version 5.0 FM Transmitting Frequency: 87.5~108MHz 9. Voltage Detection