Key Features:Dual Use: This water storage bladder not only holds water but also offers effective filtration. You can use it with or without the hollow fiber membrane filter, depending on your water source.Compatibility: Easily replace the internal bladder in your existing hydration vest or backpack with this upgraded option that provides filtration capabilities. It can also be used as a standalone water bladder for maximum flexibility.Filtration & Storage: Simplify your outdoor adventures by opting for a system that delivers both filtration and storage in one compact solution. This eliminates concerns about packing too much or too little water.Effective Protection: Featuring advanced filtration technology, the 0.1-micron hollow fiber membrane protects against 99.99% of bacteria, as well as protozoa, parasites, and other waterborne contaminants.Adventure On: Whether you're looking to enhance your existing hydration backpack or need a new portable water bladder, the Puribag Adventure Bladder ensures you stay outdoors longer with reliable access to safe drinking water. Included in the Puribag Adventure Bladder:1x Puribag Adventure Bladder (2 liters)Hollow fiber membrane filter (optional use)User manual for optimal usageUpgrade your outdoor experience with the Puribag Adventure Bladder-the perfect blend of functionality and convenience for hiking, backpacking, biking, and beyond. Order yours today!