If you're on the move and exerting yourself, you need instant and easy access to fluids that won't slow you down.__ The Vango H2O 20 is a compact, lightweight rucksack that incorporates a 2-litre hydration bladder in a separated compartment, so you never need to go thirsty.__ The pack's 20-litre capacity gves you ample room for essentials, and the combination of Vango's AirForce back system and Air Mesh construction keeps you ventilated and comfortable. __ A detachable bright orange rain cover, with reflective print, protects the pack from downpours and helps keep you more visible if you're running at dusk.AirForce back system - constructed using raised foam air channels covered with highly breathable Air Mesh to create a 'chimney' effect enhancing ventilation Contoured Air Mesh harness for comfort and breathability Zip access to main spacious compartment Two front zip pockets Helmet stow compartment Detachable waist strap Light coloured lining makes finding dark objects easier Dura flex vee buckles - super strong and light weight More info