Digital Innovations AcoustiX USB Powered Speaker System &ndash; Magnetically Shielded Stereo Speakers with Sound Bar Configuration (4330200) Magnetically shielded to prevent interference from PC, monitor or TV USB powered  use your laptop, PC, TV, monitor or other device USB ports (no power plugs, wall warts, or ac/dc adapters required) 1.5 watt per channel of high-quality stereo sound Volume control, On/Off switch and power indicator light Speakers can be configured as a sound bar