Berryman Intake Valve and Combustion Cleaner ? Professional is formulated for use in all fuel-injected gasoline engines. Contains polyetheramine (“PEA”) to clean combustion chambers and ALL types of intake valves in, including those in PFI, TBI, and GDI engines. Dissolves carbon. Restores original octane requirements. Can be applied through both air-intake and vacuum induction system using universal application accessories. Safe on catalytic converters and oxygen sensors. Offers same benefits as 2611 but bulk-packed specially for the automotive professional. Contains 6 aerosol cans with hose assemblies, 3 reusable application accessories kits, and 2 full-color, dual-language instruction sheets in English and Spanish. Recommended service interval is 15, 000-30, 000 miles, as required. Not for use in diesel engines.