Heidi Powder x System is a combination of cementitious and silicate based materials used on negative side surfaces to seal and stop leakage caused by hydrostatic pressure. It is a 3 coat, two component system consisting of one powder and a liquid. It's a dry powder that hardens in seconds when exposed to water. Heidi Sealing Liquid penetrates through Heidi Powder x into the capillaries of the substrate. It reacts with moisture and the constituents of the substrate to form crystals. While moisture is present, the crystallization process will continue for approximately 6 months. It's not designed to be used as a wearing surface. Horizontal surfaces subject to vehicle or heavy foot traffic must be covered with a protective topping.