This product is a blend of acids & detergents specifically formulated to remove excess grout after tiling, & is suitable for both porous & non-porous surfaces. Unlike conventional acids, residual grout remover is not hazardous to the user during the cleaning process, & contains inhibitors to prevent attacking any metal components associated with the building. Residual grout remover s powerful formula is extremely cost effective due to it s dilution ratio. Covers up to 90m 2