Why Choose This Performance Hydration Backpack?This lightweight and durable Hydration Pack has lots of intelligent features: Quality water bladder technologyInsulated water bladder and hoseBreathable backpack shoulder straps & 420D Ripstop Fabric is tear & water resistanceSafety whistle for emergency situationsReflective safety tabs help keep you visibleEasy access outer mesh pocketExternal bungee straps for additional carrying - eg helmets and jacketAdjustable backpack chest and waist straps to ensure the perfect fitErgonomic side stabilizers on the waist strap hug your body keeping the pack centered and anchored to your coreKey attachment clip to keep your keys secureShut-Off Bite Valve is Easy to Use & Won’t Leak The hydration pack Bite-Valve has been designed for ease of use: Ergonomic 90-degree angleEasy locking shutoff valve to prevent accidental leaksReplaceable silicone mouthpiece and inner sealing pieceQuick 'click-and-go' hose retainer makes it easy to drink on the goPremium Hydration Bladder The hydration bladder is made from a taste-free bladder film that is made in the USA, then assembled in cleanroom manufacturing facilities overseas. The film is made of a tough and durable medical-grade PE film.