Wireless Bluetooth Speaker with Rechargeable Battery. Compatible with MP3/4 devices, TF/USB Flash Drive, or any audio device which is Bluetooth compatible or has a 3.5mm jack. You just need to pair your phone or other music players which supports Bluetooth with the speaker. After paired, you can enjoy the music with speakers that offer you great sound quality. Moreover, if your device does not have Bluetooth function, you have no need to worry about it. The speaker’s “AUX” mode allows us to connect with any audio device, after connected, the speaker plays the music of the connected audio device. It comes with a Built-In FM Radio to listen to your favorite radio stations (How to connect FM see Manual provide with device). Rechargeable lithium battery which gives you 6 Hrs. Playing time. The microphone with allows you to make and receive the hands-free calls and listen to other parties loud through the speaker. Auto connected to call even you are playing music and auto connected to music after call over.