Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: How tall is this unit?
Document: I hope that helps you figure out how many of your shoes will work on this little unit.
The product is made of inexpensive materials but performs well as a closet shelf unit. The instructions are pretty clear to follow.I would purchase this product again
I added this unit to another that I've had in my mudroom for quite a while. It's a great organizer for regular shoes, but the shelves aren't high enough for hiking boots, which is what I'd really like.
The shelving unit is functional - I use it in my studio so I'm not too concerned about their appearance which is just okay. They sag a bit in the middle - there isn't a lot of weight on them, but I guess it doesn't take much to make them droop.
Not so easy when you're storing them in a cabinet.In comes the ClosetMaid Closet Organizer to the rescue!This fits perfectly inside my cabinet unit... and the spacing between shelves is exactly as much as I need to be able to fit the 6 pieces of Calphalon in it that I wanted to - with their lids inverted on them!
These closet shelves are a great value and perfect for closet organizing. They stack, if so desired, and this particular color seemed to be about half the cost of the same shelf unit that was offered in white and oak. I don't understand when reading the other reviews how it got a low star rating for being cheap. I found them to have fairly high quality and will probably order two more.
This unit is made of pressboard with a laminate covering. Only the tops of the shelves are covered though so the bottoms just appear as pressboard. The one I ordered came with a lot of minor damage on all of the pieces. It was fairly easy to put together but I'm not convinced it is going to last very long as a shelf for shoes at my front door...  For the $ I would have been better off going to Gothic Cabinet and Craft.
These were exactly what I thought I was getting and they were very easy for me to put together. They will not hold tall shoes (boots/heal) on the inner shelves. They look nice in my closet; I am very happy with the product.
you get what you paid for.... would have expected more from closetmaid. I would not buy this again or possibly anything else from them.
worst furniture piece I have tried putting together. It absolutely refuses to assemble and once I finally had it together to operate reasonably for me, it came apart in under 3 days. Please, if you value your time, energy and money, do not buy. you will have better time putting together a vintage muslce car then this. And the car would last longer! !
Answer: It measures 12" from top to bottom and 6" between shelf and bottom and shelf and top.  Hope this helps.