Power Plus fuel fragrances are designed to eliminate unpleasant exhaust odors and the eye, nose and throat irritations that come with them. Pre-mix with fuel or pour directly into your tank before filling up. Power Plus Lubricants fuel fragrances are safe for all internal combustion engines, injectors, carburetors, 02 sensors and catalytic converters. They do not inhibit or enhance engine performance. One 4 oz. bottle treats up to 35 gallons of alcohol/methanol, 20 gallons of gasoline or nitro methane or 10 gallons of diesel fuel.