Robust and Durable: The greenhouse is made of strong and thick metal, and the surface paint treatment to prevent oxidation and rust. The connection is reinforced with metal rivets, a durable structure enough to hold all kinds of books. . Adjustable and Extendable Bookends: The adjustable bookstand can expand up to 48cm (18.89in) and contract up to 11cm (4.33in) to meet various needs. You can adjust the length of the bookends according to the number of books you need to store. . Practical Design: Bookends divided into three compartments, it is more convenient for you to classify books and articles. The edge is designed with a smooth arc without scratching your desk or books. . Make Your Desktop More Rank: The simple and elegant design can store your books well, and the simple patterns can also be used as desktop decorations to make your books more tidy. . Wide Range Of Uses: Adjustable book shelves are used to hold magazines, books, DVDs, binders, etc. very suitable for childrens room, home office, library, also a first choice gift for children and students. .