Kittrich Clear Silicone Jumbo Stretchable Waterproof Book Cover Clear jumbo silicone book cover with reinforced corners. Perfect protection for hardcover text books and binders (not for use with paperback books) If applying to a book with a bookjacket, please remove bookjacket prior to application Washable markers can be used on silicone bookcover to make notes and will wipe away easy with a damp sponge Fits books from 8" x 10" up to 3 ring binder size.