Spectre's HPR (High Performance Racing) universal cone diesel air filters are designed specifically for the air flow and filtration needs of your diesel engine. We designed the media in this air filter for exceptional air filtration to protect your diesel engine while still providing increased air flow over a standard paper air filter. These washable cone filters come factory pre-oiled and ready to use, with multiple flange size and heights available. Spectre's HPR diesel air filters are available in red, blue or black. These universal clamp-on air filters are easy to install with no special tools or skills required.