Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Don't be misled.

It was only when I purchased and received this unit that I understood how it worked and that "phone jack extension" meant it was a receiving unit dependent on a transmitting unit which plugs into an existing phone jack. I was naive in thinking it could be a standalone marvel of advanced circuitry and technology. Shoulda' read the fine print but I don't believe it's explained in the promotional copy that it's part of a two-box "system."Buyer beware. But I must add that my trust in shopping at Amazon was increased by the no-questions-asked return policy which was so efficiently and swiftly applied. No deceptions there!