Leak proof and Odor Free Hydration Bladder:ROCKBROS hydration pack included 2L /70 OZ leak proof sealing water bladder. The nozzle cap can be locked by pushing it down and unlocked to drink which prevents spills. Premium material without strange flavors from the bags. It is easy to fill,disassemble and clean with large opening Satisfy Your Thirst:The water reservoir with 1M /39.4IN soft drinking tube,which makes it is easy to suck water out of the pack. 2L leak proof sealing hydration bladder could hold -20°C-50°C water. Offer any essential water to kept you hydrated. Just enjoy the hiking,running,cycling and festivals fotget thirsty Breathable Hydration Backpack: The breatheable shoulder straps and air support light back panel will keep your shoulders from overheating even you live in the south where heat and high humidity is a daily struggle Lightweight and Compact:Only weight 340g for the hiking water backpack and water bladder,ultra lightweight. You won’t feel any burden on your shoulder. The side of the pocket is big enough to fit not only your keys, cash, sunglasses , phone but also a fairly clunky portable charger Ergonomics Design:Long adjustable chest buckle,compact 3D design which allows it to secure the hydration packs to the body,the water tube will be fixed on the shoulder strap,it won’t shake when you are travelling outside. Reflective logo will keep you visible at night,also you may attach a taillight on the water backpack