This high density ceramic allows your EVA Advanced Water Filtration System to filter & retain impurities up to 0.2 micrometers (the size of infectious germs like salmonella, E-Coli, shigella, etc) It is recommended that you check the state of the ceramic when replacing your filter cartridge, but with a proper maintenance the ceramic can last between 24 & 36 months. Some parts of the EVA Advanced Water Filtration System have to be periodically removed & changed to maintain a perfect filtration process. With a proper maintenance the ceramic can last between 24 & 36 months. replacement part ceramic filter