That’s certainly true for C2 Guard, a non-toxic waterproofer, sealer and primer designed for use on unsealed wood and concrete surfaces. Its unique formula absorbs deeply into the surface, forming a flexible polymer barrier that becomes part of the cellular structure. This enhanced cellular structure helps prevent the effects of mold and mildew, dry rot, cracking, peeling, cupping of wood. For concrete C2 Guard helps prevent concrete corrosion and spalling, the effects of mold and mildew, the effects of pool chemicals and eases ice and snow removal.