In an existing wall, sometimes a stud is in the way and needs to be cut to make room for the MantelMount RB100 Recess Box. The remaining studs in the wall might be too far apart for the Horizontal Braces (that come standard with each of our MantelMounts) to reach. Our MantelMount RBE10 Recess Box Extenders easily solve this problem because they reach up to 35 inches to align with the nearest studs in the wall for a very easy install. The covers that are included with the RB100 can still be used to cover the RBE10 Extenders, and painted to match the wall.