STP Ultra 5-in-1 Fuel System Cleaner  (12 fl. oz.) (Case of 6) 5 in 1 Fuel system cleaner deep cleans entire system and lubricates engine parts This formula is scientifically engineered to enhance your motor oil's effectiveness Formulated to help maximize protection levels and performance Works with modern gasoline engines such as turbo, direct inject and hybrid vehicles Redesigned fuel additive bottles are compatible with cap-less fuel tanks