HIGH QUALITY HYDRATION PACK--Back lining and shoulder straps are all made of lightweight, breathable mesh nylon fabric, the hydration backpack can keep your back dry and comfortable for outdoor sports.And its double built-in waist straps improve its wear and tear resistance to ensure the packs life last longer.2L WATER BLADDER--It is great alternative compared to a water bottle.You dont need to carry too much stuff and make your normal backpack full of bottles when you are hiking/walking/running.This is very helpful for you, it makes feel less trouble carrying multiple water bottles and also saves your time and energy.COMFORTABLE ADJUSTABLE STRAPS-With soft shoulder straps,the adjustable hydration backpack suitable for men,women,and kids.Wide shoulder straps design with loop for hose setting help you to reduce the burden and keep you wear it for hours .When you tighten it against your body you barely no its there.EASY TO USE AND WASH--Its easy to fill the bladder with 2 liters of water because the mouth is wide.That also makes it easy to clean.Backpack and water bag are separate.You can take the bladder out from the backpack to wash separately.The backpack could wash by machine but bladder be not.GREAT CHOICE FOR OUTDOOR SPORTS AND TRAVELLING--Large capacity water bag + portable backpack.Filled with little ice cubes,the bladder make you cool down for a long time in summers activities and travelling.Its good helper for running,biking,hiking,cycling,climbing, or campingin adventure.