I use them to hold paint cans and tools on the floor but you need to balance them properly as they are quite narrow. They come with a wall anchor but I need to find a suitable place to mount them. I put the heaviest items on the lower shelves and the lighter items on the upper ones. There is enough space at the top for larger and lighter items. There is not enough space between the shelves for full-size storage boxes. They fit into shorter compartments that you could use to store files (like the height of those manilla folders). I had no problem bringing them together with a few light taps with a rubber mallet.