Sawyer Mini Filters are durable, lightweight and versatile. Capable of filtering bacteria like the dreaded Giardia (Bever Fever) and more. No moving parts to break if dropped. Bright colors to choose from so you don't lose it. Can use as an inline filter on a hydration bladder set up. You can also create a gravity filter setup using a hydration bladder. Sawyer Mini will screw directly onto a water or soda bottle too. It comes with a rollable 16oz pouch that it screws onto as well. Little Filter, Big Options.