I was painting a room and wanted to replace the existing single box with a double box in the finished wall, but as most boxes have external mounting tabs/nails the big problem is that you have to remove enough drywall. to fix the box. This one with internal mounting screws worked great! I traced it on the wall with a pencil and carefully cut out the desired shape with a vibrating saw. I think I got a bit lucky because one day I was able to remove a group's nails and pull them out without damaging anything. At least one other reviewer commented on holes labeled for different sizes of individual wires. I didn't read any reviews before purchasing and installing because I realized that this seemed to be the only box with the option to install in the box and I knew I needed it. Regardless, I caught the wire markers and used the correct hole but almost didn't catch it. This is the first time I see something like this. I thought about lowering the rating by 1 star, but other than that quirk I would rate the box 6 stars out of 5 :) Thanks to the folks who designed and built the heavy box that saved a lot of hassle from die finished wall!