7 LB, #549, Sub Floor Patch Skim Coat Feather Finish, Prep Prepare, Easily Fills In Ridges, Gouges, Depressions Seams All Most Any Sub Floor, Use Over Any Surface Dries In 15 Minutes, Installs From Feather Edge To A Depth, Easy To Mix By Adding Water, No Primer Or Additives Needed, Portland Cement Based, Will Not Stain Or Mildew, Exceptional Bond To Concrete, Wood, Terrazzo Ceramic Tile, Coverage At 7 LB Unit Covers Up To 24 SQFT At 1/8", When Skimming Over Concrete, Coverage Is 70-100 SQFT Over Plywood, Up To 198 SQFT Can Be Achieved.