Latest Bluetooth 4.0 wireless transmission protocol supports up to 10M high-quality,stereo music enjoyment Auto switch between phone call and music Your headset will automatically switch to calling mode when calls coming even if you are listening music Built-in rechargeable lithium battery Recharge by using the universal mini-USB cable¡ªeven while you¡¯re still playing,3-hour charging,16-hour enjoyment or 20-hour calling. Interface: bluetooth 4.0