Size: Large: 18.9*12.6 inch XX Large: 25.2*16.5 inch Materials: Nylon, mesh, PVC Features: Wet Pocket It's big enough to hold your valuables such as cellphone, sport watch,wallet. Waterproof Zipper It can protect your item by preventing water from seeping into the zipper teeth. Multi Pockets Two mesh pockets to store your swimming goggles, allowing them to dry quickly and preventing mould. Hand Carry Handle The hand carry handle design makes it more convenient to use. Barrel-lock Closure The top secure barrel-lock closure provides quick and easy access to your gear. Adjustable straps Adjustable straps allow you to customize the length of the straps to suit your body shape and size. The WANDF Swim Mesh Drawstring Backpack is good for for Swimming, Gym, and Workout Gear. The gym Backpack is lightweight and sturdy. The mesh design is suitable for wet or sweaty gear to quickly dry and avoid unpleasant smell. The multiple use pockets meets different needs.