I have been searching for the "perfect" storage units for all my art and crafts supplies, which is a lot, I mean, a ton! I have some of the storage boxes this unit holds and I love them, but having them stacked one atop the other has posed problems. These units are wonderful. I have stacked 2 units together and being able to take one box out at a time is great. I no longer have to take numerous boxes down to get to the bottom one as these sit on their own plastic rails, separating each box. These are good looking (I ordered the white ones) and a great organizational tool.