This 4 piece kit includes two air cleaner adapters to adapt 5 1/8 inch neck (2 or 4 bbl carburetors) air cleaners to 3 inch and 2 5/8 inch 2 bbl carburetor necks. Also includes two air cleaner risers that combine for three height adjustments to help space the air cleaner upward to clear throttle or transmission linkage.