Premium Guard PA5578 Cabin Air Filter Our premium filters trap up to 99% of airborne contaminants before they enter the interior of the vehicle through way of the heating and air conditioning system. Premium Guard cabin filters prevents harmful spores and pollen from entering the vehicle cabin while keeping passengers protected. We have maximized the filtration area in our cabin filters without affecting the free-flow of air into the passengers' cabin. Eliminates smelly odors developing from a failing filter