Wynn's Formula Gold Engine Treatment is a chemical treatment completely soluble in oil that has a double action: it increases compression and reduces wear. It helps extend engine life by reducing oxidation, friction, and wear. This treatment improves the compression and the viscosity index of the oil and prevents premature thickening of new oil. It also reduces the build-up of sludge and deposits, helping to keep the oil system clean, and reduces oil consumption and emissions. Compatible with Petrol & Hybrid petrol, and Diesel & Hybrid diesel engines. To use, add the entire contents to the engine oil. One bottle treats up to 6 liters of engine oil. For best results, use at each oil change.