Air Filters › REPLACEMENT FIRE RESISTANT AIR FILTER REPLACEMENT FIRE RESISTANT AIR FILTER $20.95 Thick, flat foam, greaseless sealing ring ensures maximum contact with your airbox while acting as a breathable gasket for increased air passage. Quantity: Purchase Added! Thick, flat foam, greaseless sealing ring ensures maximum contact with your airbox while acting as a breathable gasket for increased air passage.