In order to properly clean an air box, you need to remove your air filter and clean the whole air box with cleansers and water. The No Toil Airbox Cover is made out of a hard, composite material that completely covers your air intake and won't allow any liquids to penetrate to your intake. The contact point on the air box cover has a strip of soft rubber that creates an impermeable seal. Simply remove your air filter and install your air box cover. Your air box is now ready for cleaning with No-Toil Air Box Cleaner.