These shelf dividers were designed to be used on a 2” Trimcase sold by Demco. I chose these because the plastic is very rigid and will not collapse from the weight of the books. The divider can also be used on binders, magazine boxes, and any other solid surface. The images are in a Word document and can be sized to fit your needs. Simply print, trim out, and Mod Podge to your surface. Here is the link for the Trimcases so you can see what I used. www.demco.com/demco-reg-cut-corner-trimcase-tra