Hydration Water Bladder Capacity: 2.5 Liter ; Size: 45 X 21cm; Net Weight: 300G Two Layers Cargo Design, One for Hydration Bladder, and the Other for Extra Carrying Purpose. Tactical Backpack Constructed by Waterproof 600D High Density Nylon Material and with the High Quality Bladder, It Can keep the Water Cool for Hours. hydration bag, running bags, water bag for bike, riding water bag, hydration bag for bike, water bladder, running hydration bag, running water bag, hydration backpack, hydration bladder.