Guardian™ Gravity Water PurifierDescription State of the art virus protection in an easy, high volume gravity system. The Guardian Gravity Purifier has you covered with safe water around the world, removing viruses, bacteria, protozoa, sediment and microplastics hands free. Simply hang it while you go about your tasks at the hostel, basecamp or campsiteits 10L reservoir supports the daily water needs of multiple people. Originally designed to protect servicemembers in the field,