ezyoutdoor 2L Reservoir Hydration Pack Resevor, Bladder for Camping Hiking Picnic Backpacking Walking Survival Hunting (blue) BPA-FREE and food-grade antibacterial bladder material;For sport bags like running backpack, hiking backpack No risk of leaking, wear-proof and pressure tolerant;Comes with a dust cover to keep the water hydration bladder from pollutants. Smooth interior preventing bacteria and lime build-up;For water temperature from -20 to 50 degrees Celsius. Water capacity and exercixe load is a contradiction.The greater the capacity of water bag, a single can carry more water, but because of the weight in motion process use more energy. Based on the cross-country,cycling,hiking,water consumption of comprehensive study, 2 litres of water bag is to get the best in the balance. Package included : 1 x 2L Reservoir Hydration Pack;Lifetime Warranty7-15 days delivery date with tracking number by USPS