CORKSPORT Dry Flow 3" Outlet Air Filter - Dark Gray (Gen-6-477-10) Oil-free filtration media: The unique non-woven filter media does not require oil to filter and trap dirt and actually sheds dirt under engine vibration unlike cotton-gauze which holds contaminates until you clean your filter. Polymer mineral reinforced internal framework: Retains form when compressed or bent and prevents filter collapse under extreme vacuum created by turbocharged engines Easy Maintenance: CorkSport dryflow air filters are easy to clean, requiring only a mild all purpose cleaner and warm water. CorkSport filters can be knocked a few times to remove excess dirt off of the filter pleats. Our non-woven filter media resists water absorption and can withstand almost unlimited cleanings Specifications: The CorkSport 3" Outlet filter has a 4.75" filter media length, protrudes 6 from end of fitting to which it is attached and is 6" at its largest diameter.