A:AnswerI found the spec to be accurate aproximately 2.75 inches. Also keep in mind you need to add to that the depth of the TV itself to determine how far the TV will extend from the wall. In my case the mount plus the depth of the TV equals about 6.5 inches total.
Incidentally this is a Good unit for the price.
A:AnswerYes it should work with your tv.
It also comes with the screws for the tv to mount as well as the bolts to hold the mount on the wall also a cheap tiny level