This 2.5kg Mapei Flexible Wall & Floor Grout in Charcoal is a cement-based grout suitable for various applications including underfloor heating, timber floors, ceramic tiles, concrete, natural stone, plaster, plasterboard, and porcelain. It is designed for joints up to 6mm and can be used on stable timber floors. The grout has a pot life of 2 hours and sets in approximately 24 hours. It is suitable for both interior and exterior use. Each pack covers up to 8 m² on average.