For use on Fiberglass, clear epoxy and previously painted surfaces. Apply Fiberglass Surface Prep YMA601 to a damp sponge or 3M® maroon Scotch-Brite® pad. Then scrub the surface to be cleaned using moderate pressure. Wipe off with a clean, wet cloth ensuring that no traces of Fiberglass Surface Prep YMA601 remain. Repeat until all residue is removed, changing cloths frequently. As soon as the surface is dry, it is ready to paint. Before application of the primer it is very important that all contamination has been removed. To be certain the contamination has been removed, run water over the surface, if the water beads up or separates, wipe again with Fiberglass Surface Prep YMA601. If more than 4 hours pass without overcoating wipe with a clean wet cloth and allow to dry.