Product Description Size: before storage: 41*24*16cm after storage: 12*7cm Color: green, black, sky blue Material: water-repellent polyester fabric 【Lightweight and Compact】The foldable backpack can be folded into a sandwich size and put into a compact bag, saving space in your suitcase. It is your best choice for short trips or walking with pets. 【Waterproof Backpack】This 18L hiking backpack is made of high-density nylon, which is durable and waterproof. Waterproof zipper and waterproof tape, cut off the rainwater from the fine spots in the bag. The nylon used can prevent the hiking or trekking backpack from being scratched when climbing branches. 【Comfortable】Designed with comfort and function in mind. Breathable mesh shoulder straps relieve your shoulder. The length of the shoulder straps is adjustable. 【Versatile】The foldable backpack is perfect for outdoor activities such as: day trips, short hikes, fishing, hunting, skiing, skating, swimming, school, shopping, gym, etc.