USG Durock Brand Multi-Use Self-Leveling Underlayment is a pre-sanded cementitious underlayment for use in multiple interior applications. Additional features include: fast application and fast setting allow for return of light traffic within hours; no shot blasting required for most applications; ideal for wood frame, renovation and light-commercial construction; meets resilient floor industry specifications for underlayment under commercial goods; exceptionally smooth; and crack-resistant.