Hang Tight Hanger System
Simply level the mount to your liking and using a skill saw, cut a perpendicular cut on the back of your mount to be hung. Place the L bracket with slot over the cut and screw it in place. Now take the wall bracket and attach it to the wall so it is also perpendicular to the floor and screw it in place. Make sure it is in a stud. Then it is as easy as hanging the mount on the bracket. Absolutely no rotation of the mount what-so-ever, it is fool proof.
LARGE 3 1/2"