1. Active Speaker - Optional external battery or usb power supply for the speakers . 2. Charging functions - in an external USB power supply for the speakers at the same time, the home theater can also charger iPhone/iPad console. 3. Telescopic speaker - telescopic design, which will help furnishings, high-grade appearance. 4. With the audio input port, it can be used as amplifier when you connect it with MP3/MP4. 5. With 1pc 1000mm USB power cable.