These soft, silicone tubes are ideal for the outdoors and anywhere the next adventure takes you. The integrated hole allows them to be securely attached to a bag or backpack with a carabiner (not included) in seconds. Food-safe (FDA), 100% BPA-free and phthalate-free, they are rugged enough for a backpack and soft enough to allow all of the contents to be squeezed out. The selector cap makes identifying contents a breeze and the large opening makes refills quick and easy. Airplane carry-on approved sizing ensures worry-free check-ins.