The Katadyn Vario Ceramic Prefilter Disc, also known as part number 8015035, is the replacement ceramic disc for the Katadyn Vario Microfilter. Disc should be replaced when the ceramic has worn down so much that the plastic is showing.
The purpose of the Vario Ceramic Disc Prefilter is to block larger particulates before they reach the pleated filter cartridge. The Vario Disc Replacement is also cleanable, so when pumping becomes difficult you can just clean the prefilter instead of having to immediately replace it.
The Katadyn Vario Replacement Ceramic Filter Disc comes with: