Model of a modern signal mast with a platform and ladder, as used on most modern North American Railroads, in N scale. This particular model was designed for the Digitrax SNA 2-head LED signals. The mast can be mounted to  the rear of the Digitrax mast, with these signal head shields glued to the front of the signal board. This particular setup has the stairs to the rear of the signal, with an indentation in the foundation block for the Digitrax unit.