www.waterfilters.net/Katadyn-Vario-Replacement-Ceramic-Filter-Disc.html<br />The Katadyn Vario pre-filter ia a 0.3 micron ceramic disc designed to capture large particles before they reach the pleated filter cartridge. The Katadyn Vario ceramic disc is 100% field cleanable. Replace the ceramic prefilter disc when the ceramic is visibly worn to the point where plastic is showing through.
