Medium Bed Modified fully supports heavy tiles and stone, reducing lippage problems and the need for leveling or pre-floating rough surfaces. Medium Bed Modified can be built up to 3/4 Inch (19mm) without shrinkage or extended set times. It may be used for either walls or floors and is perfect for both interior and exterior applications. Medium Bed Modified is a blend of Portland cement, sand and special dry latex additives that significantly improve bond strength and freeze-thaw stability performance characteristics.