Zep Shower, Tub & Tile Cleaner dissolves soap scum, rust, hard water scale and other substances that build up over time on tubs, showers, sinks, faucets and other bathroom surfaces. The cleaner's tough foam spray reduces the need for scrubbing, while its unique formula is safe on fiberglass, acrylic, ceramic tiles, porcelain, laminate, and Corian.Directions: Test product first in an inconspicuous area on colored grout, fixtures and shower doors. Spray on surface. Wait 2-3 minutes. Wipe clean with damp sponge & rinse well. Not for use on: Marble, granite, terrazzo, natural stone. Note: Do not allow to dry. Prolonged contact may cause streaking. Rinse fixtures immediately to prevent discoloration