When i first purchased the item it advised that you can put it straight into the drywall. I wish they would include how to make it the most rigid because they barely hold any weight. For a heavy duty/sturdy application we first added a 1 by 4 to add stability. We then screwed through the clip and into the drywall at every stud as well as between studs (into the 1 by 4). The only thing that will fail now is the iron shelving itself

Nice product, good closet organization solution however Rubbermaid has chosen to view the in a convenient tunnel vision, only 1/2" drywall is supported, anything other than this requires the consumer to find 5/8" (in my example) drywall mollies. The Rubbermaid help line answers this question in an ambiguous manner that doesn't clearly state "Rubbermaid doesn't accommodate this, consumer must find their own solution", not very convenient.

Do NOT install this design if you ever plan to remove it to re-paint. The back clip design requires you to rip the clips out of the wall to remove, thus requiring significant drywall repair.