Having studied Tesla a great deal and always being excited about finding new information I was highly disappointed by what I received.
It was not a book but 15 sheets of paper printed, folded and stapled in the middle to comprise a 30+ page pamphlet that lacked in detail, substance and anything that cannot be easily reviewed over the internet.
The information was not about any "lost" inventions but skimmed the surface of some of Tesla's more notable patents and gave some inaccurate descriptions of their function.
This booklet contains less information than my college essay on the subject of Tesla (aside from the tiny patent photos) and in comparison to other literature about Tesla, is limited.
This booklet would be good for a small child who is interested in skimming information about Tesla, without really digging in or learning anything below the surface. For those that want more detailed information I was able to purchase The Fantastic Inventions of Nikola Tesla ISBN 978-0-932813-19-0 for around $9 on Amazon and it contains over 300 pages of data and Tesla's own hand also.