DMR air cleaner covers are machined from billet aluminum then triple chrome show plated. Comes with mounting bolt. Inside I.D. is 5.5" which is standard size for most high flow air filter systems such as S&S stealth kit, some Screamin Eagle stage 1 kits, some Ness stage 1 kits, and many more. These fit S&S stealth perfectly. IF YOU HAVE A SCREAMIN' EAGLE OR NESS STAGE 1, YOU MUST MEASURE THE OUTSIDE DIAMETER OF THE FILTER AND VERIFY IT TO BE 5-1/2" OR LESS O.D.  Ness and Screamin' Eagle filters have some changes throughout the years. It is your responsibility to measure and be sure the filter is no bigger than 5-1/2" ouside diamter where the cover fits over the filter.  MADE IN THE USA!