This is the iPod dock with portable, wireless rechargeable speakers that allow you to listen to music anywhere in your home. This system uses 2 3/4" spherical, wireless speakers that operate on a wide 915 MHz frequency that won't interfere with other wireless devices. Each 3-watt speaker produces clear, vibrant sound up to 150' away from the dock. The dock accepts most iPod models and transmits music to both speakers, which serve as stereo speakers when both are listened to in the same room (mono when used separately). The dock has a 3.5 mm audio jack that allows you to plug in external audio sources, such as a TV, radio, or other music player. Each speaker has a built-in rechargeable battery that allows for up to eight hours of operation from a two-hour charge. Dock plugs into AC. 14" L x 5" W x 5" H. (5 lbs.)