Product description Material: plastic Size: 7.2*7.0*7.0cm Color: black and red Rated frequency: 3 (HZ) Rated power: 3 (W) Rated voltage: 5 (V) Expansion interface: USB interface Package content: 1 pair of notebook mini portable speakers 1.Small Size, Big SoundTwo speakers, with dimensions at less than 3 inches per side, to output full, rich audio from your PC/laptop/notebook. 2.USB Power Both speakers draw all their power through the USB connection in the cable so you don't have to worry about finding an outlet or carrying around an adapter. 3.3.5 mm Audio Plug Near-universal audio plug quickly connects to most PCs and mobile devices. 4.Volume ControlMore convenience with an in-line controller that lets you quickly adjust the volume of the speakers without having to change the volume on your device. 5.Built to TravelCompact form and durable construction mean you can have sound most any place you go; a great fit in your laptop bag, briefcase or bookbag.