Small size, good sound quality Laptop output complete, rich audioUSB Powered:??Both speakers get all their power via the USB connection, so you don't have to worry about finding an outlet or carrying an adapter with you. The USB cable is 3 feet long. 3.5mm Audio Plug: The audio plug connects quickly to most PCs and mobile devices. An audio plug needs to be connected to the computer to play sound. The USB cable is 3 feet long. Volume Control: Built-in controller for added convenience, allowing you to quickly adjust speaker volume without changing device volumeDESIGNED FOR TRAVEL: Compact form factor and durable construction means you can get your sound anywhere; perfect for your laptop bag, briefcase or school bagFull-range stereo and compact size optimized for mobile listeningEasily connect to laptops and other USB-equipped devices