The Spitfire Motorcycles Finned air cleaner is now available for CV and S&S carbs. This air cleaner is machined from 6061 aluminum, and uses a 4" filter element. Like all Spitfire parts, they are made in our shop right here in the USA! - See more at: http://www.spitfiremotorcycles.com/products-page/air-cleaners/finned-air-cleaner/#sthash.saikX3mg.dpuf