If you drank 3 litres per day this fantastic water filter will last you 345 years! The Sawyer Mini Filter which uses a microfibre filter with absolute micropores of 0.1 microns that lets the water through but filters out the bad stuff including bacteria, protozoa or cysts like E. Coli, Giardia, Vibrio, Cholera & Salmonella typhi. What you get out is clean safe drinking water. The Filter itself is quite simply the best filter for performance, size & weight with a total field weight of only 57g. You can use the Mini Filter as a straw, drinking directly from a water source, or attach it a Sawyer Squeeze pouch or your own drinks bottle. You can even use the Mini Filter as an inline filter on your hydration bladder. It has a good flow rate & comes with a 378, 541 Litre guarantee. Cleaning couldn’t be simpler, you just backwash the filter with clean water using the supplied cleaning syringe to rinse out all the bad stuff & then continue to use as normal. Ways to use this system: Attach the included drinking straw & filter directly from source. Screw the filter onto the Sawyer Squeeze Pouch & decant into a clean container. Screw the filter onto your own bottle. Use as an inline filter on all hydration bladder systems. Use a Source Convertube attached to a Sawyer Squeeze Pouch with the Mini Filter inline to create a safe hydration system