Alpha Backer Board(building panel) is the innovative alternative to traditional cement backers. Its HCFC-FREE waterproof XPS core, fiberglass reinforced and cement coating gives the panels strength and vapor-retardant, making Alpha Backer Board the perfect choice for a variety of interior and exterior applications, such as the interlayer to walls or floors and the thermal insulation board in underfloor heating systems. They can be tiled with all types of ceramic, glass or stone tile whether they are mosaic or large format tiles. Especially large and thin tiles benefit from the durability of the Alpha Foam Backer Board(building panel)and the smooth, even surface it provides. 1. 100% waterproof, made of HCFC-FREE XPS foam 2. High-rigidity and durability 3. Close bond to any tiling walls or floors 4. Compatibility with multiple substructures 5. Vapor retardant preventing mildew 6. Light-weight, easy to handle and can be cut with a utility knife