Sprinkle Corte*Clean® powder directly onto the stubborn composite stain(s) when the composite is wet with Corte*Clean®, in direct sunlight above 65 Degrees Fahrenheit. Make the Corte*Clean® powder into a paste, scrub the affected area with a brush that will not damage the composite, let the Corte*Clean® work for up to 20 +/- minutes or until the Corte*Clean® becomes dirty or discolored, then hose off. KEEP THE COMPOSITE WET WITH Corte*Clean®, DO NOT ALLOW DIRTY CORTE*CLEAN TO DRY ON COMPOSITE! Rinse with water. Water magnifies stains. Allow composite to thoroughly dry. Repeat the Corte*Clean® application process until thoroughly clean.