Harley Twin Cam Air Cleaner Cover Click the image on the left to see how the Air Cleaner Cover works with the stock Harley Air Cleaner Cover. In addition to the engraved cover, there's a billet aluminum bracket, and mounting hardware. The bracket sets on top of the ''football'' cover. Use a supplied screw to fasten the bracket & football back to the original mounting of the cover. The engraved cover has (5) holes that line up with threaded holes of the bracket. Use the supplied chrome screws to secure the engraved cover to the bracket.