These are sturdy little shelves. I purchased them for an office and was so happy I purchased a few more. The description is a little confusing. They come assembled, you literally open them up. The only thing you have to do is put the wheels on. I did them by hand about 85% and then used the tool provided to tighten them. The small cup and hooks easily snap to the rim of whatever shelf you choose. Its nice you can make that choice based on whatever your needs are. Cute, functional, relatively sturdy. :)