The MSR Mini Works EX is an expedition quality ceramic water filter. As with all MSR expedition gear the Mini Works water filter can be completely stripped down and maintained in the field without the use of tools, which makes the mini works the choice for far flung destinations where outdoor shops will be non existant. The ceramic core is charcoal filled so not only does it remove anything larger than 0.2 microns (including bacteria,protozoa, giardia and cryptosporidium) but it also removes chemical tastes and odours from the water. This makes a big difference if you are pre treating your water with iodine or chlorine to remove viruses. The Airspring Accumulator filter cartridge will filter water at about 1 litre per minute, if you pump faster than this the water is simply returned into the dirty water reservoir. The filter is cleaned by scrubbing the outside of the filter cartridge to remove the dirt. A wear guage tells you when the cartridge needs to be replaced. Cartridge life depends on the quality of the water you start with, but expect 1000-2000 litres.