I bought this but never used it. The following is from the official website: [Water-repellent/Waterproof Fabric Randoseru Cover] Color: Blue x Turquoise trim Material: Nylon fabric, excellent water resistance, wind resistance, and breathability, protecting the leather of the randoseru. Size: Approximately 48cm (height) x approximately 27cm (width, inner dimension - the actual width that the randoseru flap fits into. Compatible with large A4 file-sized randoseru.) You can easily change the cover to match your mood for the day, like changing your randoseru. How to attach: Remove the shoulder straps and attach to the flap. Hook the rubber part onto the randoseru's back hook. Pass the shoulder straps through the cover's arched holes and reattach the shoulder straps to the randoseru.