(Our Tech Blog) The playGo USB kit includes a audio sender and a audio receiver unit. Its very easy to use, a transmitter plugs into your computer’s USB port, while a receiver attaches to a set of speakers or compatible stereo equipment (stereos, speakers or headphones). The units are covered in Corian(material that is used to make kitchen countertops) and feature a cool led light along the center that glows when in use. They have a range of 75 feet. via GadgetReview
source: http://websportal.blogspot.com/2011/09/wireless-audio-streaming.html