According to the exterior dimensions this lock box is 10” deep, most walls are 3.5” deep in the framing, which means that it will not fit flush in a wall. Also notable is that this lock box is 21” wide, wherein most load bearing walls have a stud spacing of 16” on center, which means the space between the studs is only 14.5”, although newer homes usually have partition wall spacing of 24” on center, making a 22.5” stud bay, so you would theoretically be able to fit it between the studs of a non-load-bearing wall, if you could find one. Long answer but I hope it helps.