On the Rite in the Rain Monsoon Dirtbag Pen Organizer everything from the TPU material to the welded seams and joints are constructed to protect your gear... even during a monsoon! Three writing instrument slots, a large storage pocket, two pockets for cards and a reliable weatherproof zipper. Use the fully removable and adjustable hook and loop elastic strap to securely attach to your 4.75"x 7.5" or 6.75"x 8.75" bound book.FITS: Any hard cover book between 7.5" to 11" in heightSTORAGE: Three exterior pen sleeves, 2 pockets for cards, ample interior storage for phones, chargers, and other loose accessories you want to keep dry FeaturesAdjustable and removable strapWater resistant zipperIntegrated gear loop