The WaterBasics Bag to Bag Water Filtration Kit comes with everything you need to produce clean safe drinking water wherever you are. The Kit includes two Water Basics Collapsible Bags, one for collecting "Unfiltered" water and the other for receiving and storing "Filtered" water. WaterBasics GRN Line Protection and Series II connectivity, assures that the system is safe and easy to setup and use. Simply fill the "Unfiltered" bag with water from a natural, municipal or stored water source, connect the tubing with the GRN Line filter directly to the threaded opening of the "Filtered" bag. Hang or place the "unfiltered" bag higher than the "Filtered" bag, give a few squeezes on the primer bulb to start the water flow, and then sit back and let gravity do all the work for you. In about the same time as it takes to make a lemonade and kick your feet up, you can have a gallon of filtered water with GRN LINE Protection from chemicals, bacteria and protozoan cysts.