BG RF-7 is an oil treatment specially formulated to increase engine compression and power by increasing oil viscosity. It contains additives that keep oil from thickening, protect vital engine parts from corrosive damage, and help seal rings to increase compression and reduce blow-by. BG RF-7 is a specially formulated professional-use engine oil viscosity improver. Its additives prevent oil oxidation, condition seals to prevent leaks and increase oil pressure, and provide protection against wear. Warning: This product can expose you to chemicals which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm.