a2dp stereo Bluetooth, wirelessly stream music from any Bluetooth-enabled device such as your mobile phone, notebook, or other portable Audio device;USB and SD card support, aux line-in function (3.5mm), microphone input function, FM radio, and has built-in rechargeable battery;Four gear controls for volume, bass, and microphone volume (optional, X2);Has 2 mic inputs to support 2 microphones for Karaoke;Includes: one wireless microphone