Not for the faint of heart. These Skull Air Cleaner Kits are a vile and sinister addition to any ride. The outer cover is a high strength, extremely rigid composite material, chrome plated for killer good looks. These kits are complete with a K&N high flow filter element as well as any necessary brackets and hardware required for a quick and easy installation. carburetor re-jetting is required and the necessary jets are included for your convenience.