Mr.Geeker Bluetooth 3.0 Talking Knit Hat with Built-in Speaker and Mic (Colorful) Can keep your head warm in the cold winter and will also allow you to listen to music and enjoy hands-free connectivity Superior sound quality; Simply sync to any Bluetooth device and in seconds the wearer, enabling them to make/receive calls and listen to music, wirelessly Set-in MIC, available for cell phone to transmit the speaking phone to your audio devices diretly so that the user can hand free answering phone up via the device. Set-in Li-ion chargeable battery, charge via USB Cable, With Built-in Removable headphones which can be pulled out from the hat if you would like to wash the hat suitable for traveling, waiting for the bus in the cold or rocking out in your bedroom, can keep warm while listening to your favorite music.