ARDEX E 90 is a special synthetic dispersion for use in conjunction with ARDEX cement-based adhesives, such as ARDEX S 28 Neu, or ARDEX X 18.The addition of ARDEX E 90 admix produces a mortar that is elastic, has high adhesion and water repellent properties (refer to adhesive packaging for information on when to use ARDEX E 90). ARDEX E 90 mixed with cement-based adhesives extends the use of the adhesive to situations where movement is anticipated e.g. external tiling, over fibre cement sheets/plasterboard,when tiling over heated sub-floors. The ARDEX E 90 mortar can be used in both internal and external tiling applications.