5 gallons of EZ Nano Seal penetrates the surface of building materials like concrete, brick, pavers, roof tiles and locks moisture out. Water and other liquids can not penetrate while it does allow any moisture that may be under the sealer to escape. Without moisture mold and mildew won't survive. Oil and grease also can't penetrate, just think a spot free driveway. Flat rate shipping of $40, per pail, to most locations, unless we contact you.