Rislone Ring Seal Smoke Repair from Bar's Leaks increases oil film viscosity to reduce blow-by, stop exhaust smoke and quiet engine noise. This engine oil additive cushions and coats pistons, rings and bearings to reduce wear. Specifically formulated to increase oil viscosity and clean rings to prevent oil from blowing past the rings into the combustion chamber. Ring Seal works with conventional, high-mileage and synthetic engine oil in any gasoline or diesel engine. A single bottle treats 4-6 quarts of oil. Add at every oil change or every 2,000 miles.