Dylusions Dyalog Book Cover DYT62547.This is a blank cover for you to decorate. Dyalog Covers offer a stylish way to keep all your Dyalog Insert Books, Pocket Inserts, and more in one convenient location. Two interior elastic bands help keep your inside elements secure while also giving you the ability to change books easily. The outside elastic band helps keep the cover closed. Dyalog Cover measures 5.875” x 8.75”.