I got tired of my shower rod constantly falling so I made these. The reason a shower rod falls is because the walls (and metal) actually, ever so slightly expand and shrink with the changes in temperature with the changes in season. This extra lip compensates for that. Just take some caulking and apply it to the backside of these guys and stick it on the wall where you would normally try to extend the shower rod. Let it dry, then expand the shower rod and slot it into place with the slots provided. Presto-bango, no more falling rod! Enjoy.