Quantity : one set , Scope OF Application: suitable for smooth and no concave convex smooth surface such as ceramic tile, glass, smooth metal surface, etc, Please note: that not all tiles are adequate mounting surfaces, this product will not work over grout lines or on porous surfaces such as: WOOD, unfinished MARBLE, GRANITE, porcelain, wallpaper, natural stones (such as Travertines), So make sure you have "good" sur-faces available at home or office before you place order!