Norcros Rock-Tite Grout is a cement-free brush in permeable jointing compound designed for filling joints from 3mm wide between concrete, natural stone and porcelain paving slabs which have been laid onto a solid permeable base using Norcros Rock-Tite Mortar. It has been specifically developed to match the Norcros 4 into 1 and Flexible Wide Joint Grout colours to complement tiles used indoors and to create a continuous living space. It is easy to use and waste-free. Any left-over grout can be poured back into the tub and stored by covering with water to at least 50mm above its surface. All weather paving joint compound. Suitable for all types of paving slabs including porcelain. Cement free, Air-Drying. Bag can be resealed. Coverage approx 30m2 for 600x600x20mm slab with 4mm joint. Comes with the Norcros Guarantee for Life.