Simple design for dependable storage. These tubs accommodate a variety of storage needs, with an emphasis on book storage. The Open Tub is great for general purpose storage, the Large Divided Book Tub is perfect for storing large quantities of books upright and organized, the Small Book Tub is great for smaller quantities of books. Lifetime warranty! Fits the Leveled Reading Book Browser (501133). Open Book Tub measures 15"W x 12"D x 6"H.