Assembly comes with re-usable cost saving filter. Finally an air filter assembly that allows your twin 4 barrel Solex and Mikuni's to breath. Far superior in performance when compared to the oringal Nissan air filter or K&N counterparts. Flows 6 times the air of a stock filter. This air filter assembly is designed to fit into your engine compartment neatly, no grinding or cutting although the fit is close. We figured it out so you won't have to! Special feature allows the use of short style velocity stacks to help straighten the air flow before entering the carburetor and you know what that means... more power! Velocity stacks can be purchased with or without the assembly. Price is for Air cleaner, drilled back plate and gaskets only. Note: There is no provision in the back plate for PCV hose mounting. There are after market PCV filters that can be attached to your valve cover breather outlet. Venting directly into the air filter can damage the assembly. Click here to view SU 2000 version of this assembly.