As with buying any component a little research is required on your part.
To be blunt i've never heard of Power Tree, looks like crap to me after a quick google.
180 joule protection! seriously mine has 10x that.
If you had bothered to do any research you'd have quickly realized that. APC,Cyberpower,Belkin,and TrippLite are the most widely known/used.
You would also know that spending $100 would get you a reliable unit that has a replaceable battery and application software.
And yeah that's for exactly what it says it's for.
What don''t you understand?
Lots of people have phones and all-in-one fax/printers.