Thick, flat foam sealing ring ensures maximum contact with the airbox, while acting as a breathable gasket for increased air passage. Exclusively formulated adhesive withstands repeated cleanings, even with harsh solvents and biodegradable oils/cleaners. Fine open-pore inner foam acts as a second filter to trap the smallest particles while ensuring maximum air passage. Fused outer and inner elements prevent dirt and grime from being lodged between layers. Includes two foam FilterSkins for easy cleaning between rides.