Arlen Ness Derby Sucker Air Filter Kit Without Cover Chrome 91+ Harley XL Standard Filter 18-384 Unique air filter kits feature a five-hole mounting system, which allows twin cam derby covers (not included) to be bolted on as the outer cover Pre-oiled filters Available in two styles: standard or stainless-steel jacketed All kits include patented ness hidden Breather Big sucker backing plates in either chrome or powder-coated Black wrinkle finish Note: exempt per C.A.R.B. Ref. E.O. D-639-2 for many 97-09 EFI applications