Powerful bluetooth IC,More stronger compatibility Powered by built-in rechargeable li-ion battery via mini USB port , long working time and low consumption. ( not included) You can through your car stereo and answer phone call via the built-in Mic. Specifications: Bluetooth v3+, Class 2 Support A2DP V1.2 Powered by USB 5V DC Built-in microphone Support A2DP stereo 3.5mm stereo inlet socket Sleep mode for energy saving Support Bluetooth hands-free function Wireless music receiver connects to 3.5mm headphone jacks Use with home stereos/speakers, car stereos,headphones etc. Colour:Black Material:Plastic Package Contents: 1 * Wireless Bluetooth Adapter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. 5. High-performance AMP chip,can push the headset,and high-power speaker,applicable to all types of speakers 2. Simply connect this bluetooth audio receiver to your line-in or auxiliary input on your speakers, pair it to your Bluetooth enabled device, and enjoy the wireless music revolution. 3. Whether you want Bluetooth convenience in your car, through your home-theater system, in your kitchen, bathroom, or bedroom,etc. 1. Make your Car AUX audio sytem and Home Theater AV HiFi Surrounding system become bluetooth compatible, get music from Bluetooth enable device such as For ,For ,For ,For Smart cellphone or Bluetooth PC, Laptop,TV 4. Simple operation,3.5mm Male to Male Audio Connector or 3.5mm Male to Male Audio Cable to connect the speakers and the receiver.