Hydration backpack backpack capacity 11 liter pack volume 3 litre applications cycling trail running trekking model 2015 materials 230 d taffeta 420 d nylon carrying system independent suspension suitable for women men chest straps with chest strap adjustable hip belts with waist strap with pockets adjustable carry handle top back length 41 cm outside pockets front pocket special features reflective print expandable capacity signal whistle padded