Summary: This product is needed to create the wireless Sonos network within your home. It needs to be hard-wired to your router, and then you will need either a ZP-90 or ZP-120 or an S-5 to play your music throughout your home. Do the research on your own. If you are looking for a slick way to have and seamless access to audio files alone, this product is where it's at. If you're looking to stream movies, video, etc. you might want something else.