UPGRADED BUCKLE STRAP: keep backpack rain cover in position, Prevent backpack cover from sliding off. FOR 70 -90L BACKPACK: Length(12.9-17.7"), Width(8.6-13.7"), Height(29.5-35.4") HIGH-LEVEL WATERPROOF: Our backpack cover is made of 210t TAFFETA mixed material features wear-resisting and durable, support 8000 mm water pressure. 4-LAYER CONSTRUCTION: External fabric of backpack cover is rip-resistant that protecting backpack from scratch, dirt, sand and internal is double waterproof coated layers that keeping off water, rain, fog and snow. COMPACT: Each backpack rain cover comes with a pouch that easily to storage and not take much place VIP CUSTOMER SERVICE: FREE exchange size when backpack rain cover not match without RETURNING, FREE exchange when backpack cover get ripped Product Description Backpack dimension form Joywalker devote to supply the most appropriate size of cover to all kinds of backpacks. In the past 10 years, We found capacity of backpack between several brands is the same but the dimension is extremely different. Even the same brand, the same capacity, the dimension varies a lot. Waterproof is elementary to backpack cover Backpack is not only a umbrella for backpack, it's also a signal and protector. When student use it, it could be used to protect belongings from being stolen or lost. And if you like traveling or taking outdoor activities, it's easy to be found by others. Durable construction- Made of 4 kinds of fabrics Joywalker backpack cover features lightweight and durable. The material of Joywalker backpack cover is very complicated, it's compressed by 4 kinds of fabrics. Each of their function is different, outer fabric is waterproof and inner fabric is to enhance the structure of cover. Even the backpack cover consists of 4 kinds of fabrics, but the thickness is ultrathin. Effectively protecting your backpack and belongings from rain, water, snow, dirt and sand. Light rain, moderate rain, heavy rain is 1000, 2000, 3000mm. The waterproof coefficient of JoyWalker backpack cover is 8000mm. 8000mm is the highest waterproof grade, Ideal for any rainy activities. Backpack cover features snowproof and not freeze in the snow. The fabric still remain flexible and perfect fitted. Package include 1 x Joywalker backpack cover 1 x grey velvet pouch Backpack cover features collapsible and lightweight, only weighs 0.17 LB. Each cover comes with a velvet pouch to carry with.