4G Surface Guard for Walls is a permanent water-based impregnation system for horizontal and vertical mineral and porous architectural surfaces. The treatment transforms natively absorbent surfaces into highly water and oil repellent surfaces (hydrophobic & oleophobic). As an impregnation, it penetrates into mineral substrates through their natural absorbency and by gravity. 4G Surface Guard 4G Surface Guard is not a film forming sealant. It leaves the substrate fully vapor permeable. Once cured, 4G Surface Guard invisible to the human eye and does not change the surface friction. Correctly applied and depending on conditions, life expectancy is approximately 10 years.