Platypus GravityWorks Water Filter System

What's the easiest way to filter water? Let gravity do all the work. Just fill the dirty water reservoir, hang it from a tree, and gravity will push the water through the hollow-fiber filter for instantly clean water. Collecting water from the lake or river is easy, too. Simply open the wide Big Zip opening, scoop up water, and close the reservoir. Then open the hose clamp to control the water's flow into the clean water reservoir. The system is field cleanable, too. Simply backflush the water b