USB 2.1 Channel Portable SpeakerEncore USB-powered 2.1 channel portable speaker, users will no longer be required to purchase a sound card but be able to enjoy digital sound and music through any computers that has a USB port. Its portability and minimal-power-consumption design allows the user to travel with it to anywhere. Plug and play installation compatible with Windows 2000/XP and OS 9/X. Simply connect the speaker to any open USB ports, Windows will automatically load the driver for it and configure this speaker as the default audio output device. Features & Specifications- Connects and draws power straight from USB port. No need to plug in to an external power source. - Compliant with USB 2.0 & USB 1.1 Specifications - One 2 inch Sub-Woofer Speaker & two 1 inch Satellite Speakers all in a small, compact, easy-to-carry design. - Perfect for the laptop. - Built in sound card. It can be used even if your computer has no sound card. - High Performance 48KHz Sampling Rate for crisp