Q2 surface conditioner and primer converts rust into a protective polymeric coating. This is a necessary product to be used anywhere rust has appeared or is a problem. Q2 converts iron oxide to a black ferro-organic coating that incorporates the rust as part of the coating. Apply with brush, roller or spray. For extremely bad rust or rust in cracks or crevasses, two coats may be needed to assure the complete conversion. A top coat will be needed where surface is dry and tack free. Apply an appropriate primer if your top coat is a latex based product to prevent bleed through. Q2 is not corrosive to human tissue and is very safe to use. Remove all rust scale or heavy rust before applications.