"TRENDnet's Powerline 1200 AV2 Adapter, model TPL-420E, creates an extreme performance Powerline 1200 network using an existing electrical system. Two adapters are needed to start a network. No CD installation required encrypted TRENDnet adapters auto-connect out of the box. Plug in the first adapter and network it to your existing router. Plug in other adapters on the same electrical system and they auto-connect to the first adapter for immediate internet access."