Air Cleaner Adapter 2 BBL 3 1/16 to 5 1/8 for Oldsmobile Engines 330 350 455 Part Number MCC153Bolds Air Cleaner Adapter is Approximately 1/8 Inch Thick Plastic This Air Cleaner Adapter Has A 5 1/8 Inch Air Cleaner Flange And A 3 1/16 Inch Carburetor Flange This Air Cleaner Adapter Is 1/2 Inch Tall And Will Raise Your Air Cleaner Slightly For Customers With Two Barrel Carburetors With A 3 1/16 Air Cleaner Neck Size That Want To Run Any Of Our Air Cleaners, With This Adapter You Can Run "Any" Air Cleaner We Sell On Your 3 1/16 Inch Neck Size Two barrel.