Black EZ-Clean Membrane™ Replacement Filter Cartridge for 1.0 l Katadyn BeFree Water Filtration System, Black Edition. It also works with the 1.0 l Katadyn BeFree Tactical bottle. It features a 0.1 Micron Hollow fiber filter that can filter up to 1,000 liters of water, depending on the water quality.

In case you ended up here by accident and have no idea what we’re talking about, a bottle with this kind of a filter eliminates bacteria and protozoa from water. So you can drink from a puddle.