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Used with Levelrock® Brand floor underlayments, USG Levelrock® Brand Acrylic Concrete Primer is a high-solids sealant that is used to coat concrete and precast concrete subfloors prior to installation of USG Levelrock® floor underlayments. Concrete surfaces tend to be highly porous. Without first sealing a concrete substrate, the bond with and surface smoothness of the floor underlayment poured on top could be adversely affected. This product is available in 5-gallon pails from USG’s Gypsum, OH facility and in 53-gallon drums and 275-gallon totes from USG’s Walworth, WI facility. Note that coatings typically assessed using the PCR for resinous floor coatings include additional coating layers (i.e. basecoat and topcoat) beyond those manufactured by USG