Hydration backpack straps chest strap wheels none bag feature suitable as cabin luggage iata norm material properties water repellent material style sporty inner material synthetic fibre capacity 12 litres backpack capacity 12 liter pack volume 15 litre applications trail running running cycling model 2015 material 70 d ripstop nylon tragesysteme motion fit trail twin link suitable for women men chest straps with chest strap adjustable hip b