Review on Efficient Over-the-Toilet Storage Shelf with Adhesive Base - White Bathroom Organizer for Space-saving and Easy Organization by Rachel Marie

Easy to assemble (two small screws). It is either attached to the toilet lid or to the wall/window with adhesive squares. I hope the glue won't leave any residue when we remove it in the future; I don't think I would recommend putting this on a painted wall but it seems to work well for tile and I put it on our glass block shower window. Please note that if you place it on a horizontal surface, it must have some space on the back for the shelf brackets to hang. I might have planned to put this on the shower windowsill so our shower essentials wouldn't keep water on the windowsill, but the shelf supports wouldn't allow for that. Not much, just FYI. Haven't tested it yet to see if it can handle a ton of weight (all the big Costco shampoo bottles) but so far it holds up with some smaller shampoo bottles, razors, soap. , and a washcloth. I will say there was some rust around one of the holes so I hope it holds up well in the shower. I'll try to update if I notice any rusting. At this point it is repainted or gifted with Rustoleum to prevent rust stains in the tub.