Dyco® HYDROPROOF™ MS is a water-based, penetrating, VOC compliant, water repellent which contains a proprietary modified siloxane. This modified siloxane penetrates up to 1/4 inch or more, depending on surface porosity and moisture content at the time of application. HYDROPROOF MS reacts with the minerals in concrete and pavers to form strong permanent bonds beneath the surface which creates a hydrophobic zone. This chemical reaction prevents water molecules from permeating, while allowing free migration of water vapors. The chemical bonds formed in this process allows HYDROPROOF MS to become an integral part of the substrate and provide long-term water repellent protection.