Kuryakyn uses only K&N and aFe oiled gauze filters in our air cleaners which, when properly maintained, are water repellent. Even so, there may be times you wish you had a pre-filter to keep bugs, dirt, wash water, or torrential downpour out of your air cleaner.; Helps prevent bugs, dirt, wash water, or torrential downpour getting into your air cleaner Constructed from water repellent and UV resistant fabric Filters debris down to .005"