Material: Oxford cloth_x000D_Dimensions (adjustment range):_x000D_Length: 20-32cm_x000D_Width: 15-20cm_x000D_Height: 30-40cm_x000D_Recommended backpack capacity: 18-30L 11. waterproof: The backpack cover is made of high-performance and waterproof oxford cloth, which can reliably protect the contents of the backpack from moisture and humidity even on long journeys! 22. Universal: Whether it's a school bag or a backpack, with this ripstop and rainproof backpack, you'll always have reliable weather protection for your daily life and travel! 33. Safe reflective: Thanks to the quick click button and reflective logo, the rainproof backpack is extra safe and provides extra protection even in the dark and night driving! 44. Ultra-light and practical: Thanks to the flexible elastic straps, the ultra-light backpack rain cover can be put on and taken off instantly and stowed away quickly to save space! 55. Best protection: With our waterproof backpack cover, we always ensure the best protection against rain and moisture in all weather conditions!