I initially bought the 24" shelves and they were too small to match the studs in my walls, these brackets weigh a lot so you can't really not have them in a stud. I then ordered the 36" shelves which fit nice however  broke 3 screws off inside the wall putting them in, they aren't very heavy duty. It was also a nightmare trying to return the 24" shelves because my order was not showing up under my purchases. Then when I finally got the return email I noticed I am  being charged 20$ for shipping which was even more annoying. This is 2017 no one wants to pay to ship anything. I won't order anything again unless I know I will for sure keep it not a customer friendly experience.