For your mosaic projects. This grout sealer is designed to protect mosaic tile grout from water, dirt, food and discoloration, although it doesn't make your project completely waterproof, so it is for indoor use only. It dries to a transparent, non-yellowing finish, and is easy to apply. Manuafactured by Mosaic Mercantile. After applying, wipe this off the tiles within a couple minutes, using a damp rag. 8oz bottle. Covers about 17 square feet.