The Rubi Delta Level System Strip is part of a system that has been developed to avoid lippage during the installation process tiles both on floors and walls. The DELTA level system also prevents the movement of the tiles during installation as well as the number of corrections in the position of the tile itself is reduced. The basic principle of the DELTA level system is that of pressing the highest piece, until matching its position with the adjacent tiles, thus obtaining a substantial improvement of the surface flatness.