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Durock™ Brand Glass-Mat Tile Backerboard is a water- and mold-resistant coated glassmat tile backerboard. The face of the panel is treated with a proprietary coating for moisture resistance and enhanced tile bond, making it ideal as a tile substrate for dry and/or wet areas Res 1 (Residential dry), Res 2 (Residential limited water exposure), Res 3 (Residential wet), Com1 (Commercial dry), Com2 (Commercial limited water exposure), Com3 (Commercial wet) as defined by the Tile Council of North America Handbook 2018. The 5/8 in. (15.9 mm) panels are Underwriters Laboratories Inc. (UL) Classified for fire resistance, and can be used in any UL Design where Type SGX panels are listed systems.