The 12.2 Quart version of these containers are the perfect size for storing mass market paperback books. I've just gone to buy more of them, because the 35 or so of them that I already have are full, and I still have more of these paperbacks waiting to be stored. Since they hold about 20 to 25 books each (depending on the size of the books), that means I have more than 700 mass market paperback books already stored, and still more in shelves, waiting to make way for larger books. I only have so much shelf space, and these small paperbacks have the lowest priority for being out in the open. It's a good thing I believe there's no such thing as too many books, or I might be disturbed at these numbers.