HIFI Bluetooth 4.1 receiver,KABI Wireless Bluetooth Audio Speaker hi fi Stereo Hi-Fi Audio Headset Lossless Adapter Welcome to use our KABI HIFI Bluetooth Receiver!It has built-in Polymer rechargeable battery, multi-function bottons, easy and convenient to use. Simply connect your smartphone or tablet PC to Bluetooth adapter and connect. Runs for an extended period of up to 8-10 hours on a full charge. No interruptions, no problems. This is Bluetooth receiver to have a 300mAh battery,allowing it to provide up to 10 hours of continuous quality music playback for car systems, home theaters, smart phones, and tablets. With any problems, please do not hesitate to email us, We will give you a satisfactory solution as promised.