"The high-quality hydration bag is made of high-quality PE and EVA materials, odorless and non-toxic, and has passed pressure compatibility testing for significantly improved durability.The large capacity hydration bladder holds 2 liters of water at temperatures from -20 to 50 degrees Celsius. 2 pack (4 liters) for all your outdoor activities needs.Leak-proof design: Upgraded soft spout with easy-to-use on/off valve to prevent water leakage. You can easily control the flow of water by biting it. If you don't bite the water, it won't leak. Quick release tube is removable. Automatically shuts off when hose is removed.Easy to clean and fill. The mouth is wide enough to hold water and add ice cubes. The bottle brush can easily access the interior to ensure a thorough cleaning of the tank liner.Widely used hydration bag is ideal for camping, hiking, biking, running, biking, rock climbing, backpacking, hunting and skiing and any other outdoor sports for easy drinking and hydration."