Mounting a Cable Pass-through box like this, with one box low enough to be out of sight and the other box behind the middle of the wall mounted TV to be out of sight, is a good way to hide the clutter of Power, HDMI, LAN and USB cables to make the wall mounted TV seem to float on air. The trick is to do it with minimum damage to the dry wall and flexibility to pass different cables between the upper and lower box when new technology and cable types require cable replacement over the years. A traditional home/office electrical outlet box is designed to clamp cables or wiring firmly which makes wiring upgrades difficult and beyond DYI. As you read other reviews of these Legrand - In Wall Cable Access Plates you'll see that this is not the perfect solution out-of-the-box (so to speak). The directions included are typical of today's shabby instruction books, which are made primarily to satisfy legal government warning requirements in six languages (DO NOT eat parts of this box because they MAY present a choking hazard and they WILL cause cancer if you eat them in California). There are two things you need to know before installing these Legrand - In Wall Cable Access Plates. First DO NOT make the hole in the wall as big as you would for a standard electrical outlet box. This Wall Cable Access plate does not mount INTO an electrical outlet box. It has its own dog-legs that grip the back of the dry wall, to clamp itself into place when you insert it and then tighten the top and bottom clamping screws. You can see from the picture I uploaded, that I initially ASSUMED it needed the same sized hole as a standard outlet box, so I traced the outline of a standard outlet box on the wall to make the hole-saw cut in the dry wall. If I had proceeded with making that large a hole, the Legrand - In Wall Cable Access Plates would have wobbled around loosely without side support. Instead, trace the hole to be the size of the actual Legrand - In Wall Cable Access Plate. In the uploaded picture, I left off the final trim plate that comes with the box to let you see the size of the opening in the wall. When the included trim plate is installed, the total instalation looks much nicer. Secondly, to make the passing of new cables between the upper and lower box possible, TRIM THE EXCESS MATERIAL off of the Legrand - In Wall Cable Access Plate. Best Buy only allows a total of two pictures with each review, so I hope you can see what needed trimming from the boxes, by looking at the single before-and-after picture of the trimmed parts. I know the makers of this box designed it so cables could not fall in from the top box, to the area inside the wall, if the cables were not connected to the TV. However, all of this extra flange material makes installation of the new cables for the first time too difficult, to make the extra material worth it. All this being said, this kind of modification I'm describing is only an option for the Do It Yourself Home Owner. From inside the wall, it looks pretty rough when you trim it like this. Someone paying a professional installer would not be happy if they saw it. Professional installers or renters would have to go with a much more expensive and hard to install set of boxes. My method described is to make the cheaper alternative work. I dropped one review Star because of the typical lousy instruction manual and the trimming necessary to get the box to work the way I wanted it to. However, once I got everything in place, I am perfectly happy with the look and performance.