Polar Bottle Cenote Hydration System  Water Storage Bladder for Backpacks and Hydration Sleeves Hydrate Better - Stay hydrated on the trail, in the field, on your bike, or just on the go, with the Cenote Hydration System Water Storage Bladder, designed to fit most bladder backpacks, hydration bag sleeves, running backpacks and hydropacks. One order contains 4 disposable water bladders, with hose and valve attachments. BPA-Free and Phthalate-Free - Made of food grade materials, this BPA-Free and Phthalate-Free hydration pack has no taste other than what youre drinking. Fill it with water, sports drinks, or even a 2 L box of wine. Leak-Free and Durable - Constructed to be totally leak free, from water bladder, to cap connector, to sturdy and durable hose, to drinking valve. Fill it, cap it and go, and know it will hold up no matter how you use it. High-Flow Bite Valve - Allowing for maximum flow, with no spills, leaks or extra work, people love the Cenote Hydration System Water Storage Bladders High-Flow Bite Valve. Just turn the bite valve to be perpendicular to the hose, bite on the clear silicone and suck. Boasts a 360 degree bite zone! Cleaning Is Optional  The durable Polar Bottle Cenote Hydration System can be washed and reused as many times as you like. Thanks to the systems unique disposable reservoir, it can also be recycled responsibly and is affordable to replace. When the reservoir is dirty, or has gotten enough use, simply recycle and replace it with a new one.