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USG Durock™ Brand Quik-Top™ White FR and Gray FR Self-Leveling Underlayment are premium fiber-reinforced poured underlayment products with self-drying technology • UL Classified and specified for use in 135+ assemblies • No mechanical preparation required for most applications • Provides smooth surface with improved impact resistance and load distribution • Enhances crack resistance and impedes crack propagation • Apply floor covering in as little as 15 hours after underlayment application • Compressive strength up to 10,000 psi (68.9 MPa) with self-sealing technology • Featheredge to 3 in. (76 mm) thickness • Suitable for most floor coverings • Can be stained, polished or used by itself as a finished floor with an appropriate coating system