This black 4 sided book rack spinner has 4 6" slots and 4 12" slots in tandem, with one of each size on each of the 4 levels of shelves. This is perfect for children's picture books, coloring books, sketch pads, as well as standard sized books. The rotating mechanism is in excellent condition, allowing for ease of turning of shelf. Perfect for a store, a library area or classroom, this shelf needs a new home.