Keep your Katadyn AC BeFree water filter performing at its best with these high-quality replacement items. Specifically designed for the AC BeFree, components that help maintain optimal filtration performance and water quality during all your outdoor adventures. EZ-Clean Membrane: Features a high-flow hollow fiber membrane that filters out bacteria and protozoa. Thanks to its design, it can be easily cleaned in seconds - no tools required - by simply shaking or swishing in water.