Review on Projector Universal ViewSonic Projectors Extendable by Mark Jefferson

I have tried this on several projectors including (Benq, Optoma) as listed. The description mentions that you can use this with projectors that have 3 screw holes. Somehow I doubt they checked it. While you can (very tricky) line up the brackets with the holes on the projector, the problem is that you can't rotate the bracket. Therefore you get a projector that is aimed at an angle of 45 to 90 degrees from your wall/screen. The listing does not state that you must be completely perpendicular to the screen after you have successfully aligned the mounting holes. . This is probably easier with a large 4-hole projector, but nearly impossible with a 3-hole projector.