The WNG-300 consists of two white noise generators combined into one unit. It can deliver two independent white noise signals (via the left and right channel) into a stereo system for true stereo sound. Stereo white noise sounds fuller and richer (sounds very similar to rainfall) than basic mono white noise. In addition, the device contains a special sophisticated filter that sharply reduces frequencies that lie beyond the range of human hearing (see spectrum analysis/oscilloscope). 

Purchase includes AC wall adapter, RCA audio cable (for hook-up to external audio equipment), and Owner's Manual. Comes with a 30 day money-back guarantee and is covered by a two year warranty.