The Level-Right family of high-strength cementitious underlayments can produce smooth level floors in just two to four hours after pouring. Level-Right, Level-Right Plus, and Level-Right FS-10 can level entire floors, new or old, and attain 5500 to 7200 psi compressive strength. They work above, on, or below grade, with no troweling required. Shotblasting or scarifying are usually not required. Maxxon Corp. 800-356-7887.